diff --git a/browser/components/extensions/test/xpcshell/test_ext_urlbar.js b/browser/components/extensions/test/xpcshell/test_ext_urlbar.js
index 3cb0511be79d3..ce2e319f4b0ee 100644
--- a/browser/components/extensions/test/xpcshell/test_ext_urlbar.js
+++ b/browser/components/extensions/test/xpcshell/test_ext_urlbar.js
@@ -188,7 +188,7 @@ add_task(async function test_registerProvider() {
 });
 
 // Adds a single active provider that returns many kinds of results.  This also
-// checks that the heuristic result from the built-in HeuristicFallback provider
+// checks that the heuristic result from the built-in UnifiedComplete provider
 // is included.
 add_task(async function test_onProviderResultsRequested() {
   let ext = ExtensionTestUtils.loadExtension({
@@ -276,7 +276,7 @@ add_task(async function test_onProviderResultsRequested() {
 
   // Check the results.
   let expectedResults = [
-    // The first result should be a search result returned by HeuristicFallback.
+    // The first result should be a search result returned by UnifiedComplete.
     {
       type: UrlbarUtils.RESULT_TYPE.SEARCH,
       source: UrlbarUtils.RESULT_SOURCE.SEARCH,
diff --git a/browser/components/urlbar/UrlbarMuxerUnifiedComplete.jsm b/browser/components/urlbar/UrlbarMuxerUnifiedComplete.jsm
index 1f382b2bfb848..53af4a7da7765 100644
--- a/browser/components/urlbar/UrlbarMuxerUnifiedComplete.jsm
+++ b/browser/components/urlbar/UrlbarMuxerUnifiedComplete.jsm
@@ -41,16 +41,6 @@ function groupFromResult(result) {
   }
 }
 
-// Breaks ties among heuristic results. Providers higher up the list are higher
-// priority.
-const heuristicOrder = [
-  // Test providers are handled in sort(),
-  // Extension providers are handled in sort(),
-  "UrlbarProviderSearchTips",
-  "Omnibox",
-  "UnifiedComplete",
-  "HeuristicFallback",
-];
 /**
  * Class used to create a muxer.
  * The muxer receives and sorts results in a UrlbarQueryContext.
@@ -64,19 +54,11 @@ class MuxerUnifiedComplete extends UrlbarMuxer {
     return "UnifiedComplete";
   }
 
-  /* eslint-disable complexity */
   /**
    * Sorts results in the given UrlbarQueryContext.
    *
-   * sort() is not suitable to be broken up into smaller functions or to rely
-   * on more convenience functions. It exists to efficiently group many
-   * conditions into just three loops. As a result, we must disable complexity
-   * linting.
-   *
    * @param {UrlbarQueryContext} context
    *   The query context.
-   * @returns {boolean} If results were successfully sorted. This return value
-   *   is a stopgap and can be removed when bug 1648468 lands.
    */
   sort(context) {
     // This method is called multiple times per keystroke, so it should be as
@@ -88,42 +70,19 @@ class MuxerUnifiedComplete extends UrlbarMuxer {
 
     // Capture information about the heuristic result to dedupe results from the
     // heuristic more quickly.
-    let topHeuristicRank = Infinity;
-    for (let result of context.allHeuristicResults) {
-      // Determine the highest-ranking heuristic result.
-      if (!result.heuristic) {
-        continue;
-      }
-
-      // + 2 to reserve the highest-priority slots for test and extension
-      // providers.
-      let heuristicRank = heuristicOrder.indexOf(result.providerName) + 2;
-      // Extension and test provider names vary widely and aren't suitable
-      // for a static safelist like heuristicOrder.
-      if (result.providerType == UrlbarUtils.PROVIDER_TYPE.EXTENSION) {
-        heuristicRank = 1;
-      } else if (result.providerName.startsWith("TestProvider")) {
-        heuristicRank = 0;
-      } else if (heuristicRank - 2 == -1) {
-        throw new Error(
-          `Heuristic result returned by unexpected provider: ${result.providerName}`
-        );
-      }
-      // Replace in case of ties, which would occur if a provider sent two
-      // heuristic results.
-      if (heuristicRank <= topHeuristicRank) {
-        topHeuristicRank = heuristicRank;
-        context.heuristicResult = result;
-      }
-    }
-
     let heuristicResultQuery;
+    let heuristicResultOmniboxContent;
     if (context.heuristicResult) {
       if (
         context.heuristicResult.type == UrlbarUtils.RESULT_TYPE.SEARCH &&
         context.heuristicResult.payload.query
       ) {
         heuristicResultQuery = context.heuristicResult.payload.query.toLocaleLowerCase();
+      } else if (
+        context.heuristicResult.type == UrlbarUtils.RESULT_TYPE.OMNIBOX &&
+        context.heuristicResult.payload.content
+      ) {
+        heuristicResultOmniboxContent = context.heuristicResult.payload.content.toLocaleLowerCase();
       }
     }
 
@@ -136,17 +95,10 @@ class MuxerUnifiedComplete extends UrlbarMuxer {
       UrlbarPrefs.get("maxHistoricalSearchSuggestions"),
       context.maxResults
     );
-    let hasUnifiedComplete = false;
 
     // Do the first pass through the results.  We only collect info for the
     // second pass here.
     for (let result of context.results) {
-      // Keep track of whether UnifiedComplete has returned results. We will
-      // quit early if it hasn't.
-      if (result.providerName == "UnifiedComplete") {
-        hasUnifiedComplete = true;
-      }
-
       // The "Search in a Private Window" result should only be shown when there
       // are other results and all of them are searches.  It should not be shown
       // if the user typed an alias because that's an explicit engine choice.
@@ -187,24 +139,9 @@ class MuxerUnifiedComplete extends UrlbarMuxer {
       }
     }
 
-    // Quit early if we're still waiting on UnifiedComplete. If it turns out
-    // UnifiedComplete doesn't need to return any results, it will call sort()
-    // regardless to unblock showing results.
-    if (
-      !hasUnifiedComplete &&
-      context.pendingHeuristicProviders.has("UnifiedComplete")
-    ) {
-      return false;
-    }
-
     // Do the second pass through results to build the list of unsorted results.
     let unsortedResults = [];
     for (let result of context.results) {
-      // Exclude low-ranked heuristic results.
-      if (result.heuristic && result != context.heuristicResult) {
-        continue;
-      }
-
       // Exclude "Search in a Private Window" as determined in the first pass.
       if (
         result.type == UrlbarUtils.RESULT_TYPE.SEARCH &&
@@ -277,6 +214,15 @@ class MuxerUnifiedComplete extends UrlbarMuxer {
         }
       }
 
+      // Exclude omnibox results that dupe the heuristic.
+      if (
+        !result.heuristic &&
+        result.type == UrlbarUtils.RESULT_TYPE.OMNIBOX &&
+        result.payload.content == heuristicResultOmniboxContent
+      ) {
+        continue;
+      }
+
       // Include this result.
       unsortedResults.push(result);
     }
@@ -326,7 +272,6 @@ class MuxerUnifiedComplete extends UrlbarMuxer {
     }
 
     context.results = sortedResults;
-    return true;
   }
 
   /**
diff --git a/browser/components/urlbar/UrlbarProviderHeuristicFallback.jsm b/browser/components/urlbar/UrlbarProviderHeuristicFallback.jsm
deleted file mode 100644
index 78b4caab9d4f6..0000000000000
--- a/browser/components/urlbar/UrlbarProviderHeuristicFallback.jsm
+++ /dev/null
@@ -1,290 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-"use strict";
-
-/**
- * This module exports a provider that provides a heuristic result. The result
- * either vists a URL or does a search with the current engine. This result is
- * always the ultimate fallback for any query, so this provider is always active.
- */
-
-var EXPORTED_SYMBOLS = ["UrlbarProviderHeuristicFallback"];
-
-const { XPCOMUtils } = ChromeUtils.import(
-  "resource://gre/modules/XPCOMUtils.jsm"
-);
-XPCOMUtils.defineLazyModuleGetters(this, {
-  Log: "resource://gre/modules/Log.jsm",
-  Services: "resource://gre/modules/Services.jsm",
-  UrlbarPrefs: "resource:///modules/UrlbarPrefs.jsm",
-  UrlbarProvider: "resource:///modules/UrlbarUtils.jsm",
-  UrlbarResult: "resource:///modules/UrlbarResult.jsm",
-  UrlbarTokenizer: "resource:///modules/UrlbarTokenizer.jsm",
-  UrlbarUtils: "resource:///modules/UrlbarUtils.jsm",
-});
-
-XPCOMUtils.defineLazyGetter(this, "logger", () =>
-  Log.repository.getLogger("Urlbar.Provider.HeuristicFallback")
-);
-
-/**
- * Class used to create the provider.
- */
-class ProviderHeuristicFallback extends UrlbarProvider {
-  constructor() {
-    super();
-    // Maps the running queries by queryContext.
-    this.queries = new Map();
-  }
-
-  /**
-   * Returns the name of this provider.
-   * @returns {string} the name of this provider.
-   */
-  get name() {
-    return "HeuristicFallback";
-  }
-
-  /**
-   * Returns the type of this provider.
-   * @returns {integer} one of the types from UrlbarUtils.PROVIDER_TYPE.*
-   */
-  get type() {
-    return UrlbarUtils.PROVIDER_TYPE.HEURISTIC;
-  }
-
-  /**
-   * Whether this provider should be invoked for the given context.
-   * If this method returns false, the providers manager won't start a query
-   * with this provider, to save on resources.
-   * @param {UrlbarQueryContext} queryContext The query context object
-   * @returns {boolean} Whether this provider should be invoked for the search.
-   */
-  isActive(queryContext) {
-    return true;
-  }
-
-  /**
-   * Gets the provider's priority.
-   * @param {UrlbarQueryContext} queryContext The query context object
-   * @returns {number} The provider's priority for the given query.
-   */
-  getPriority(queryContext) {
-    return 0;
-  }
-
-  /**
-   * Starts querying.
-   * @param {object} queryContext The query context object
-   * @param {function} addCallback Callback invoked by the provider to add a new
-   *        result.
-   * @returns {Promise} resolved when the query stops.
-   */
-  async startQuery(queryContext, addCallback) {
-    logger.info(`Starting query for ${queryContext.searchString}`);
-    let instance = {};
-    this.queries.set(queryContext, instance);
-
-    let result = this._matchUnknownUrl(queryContext);
-    if (result) {
-      addCallback(this, result);
-      // Since we can't tell if this is a real URL and whether the user wants
-      // to visit or search for it, we provide an alternative searchengine
-      // match if the string looks like an alphanumeric origin or an e-mail.
-      let str = queryContext.searchString;
-      try {
-        new URL(str);
-      } catch (ex) {
-        if (
-          UrlbarPrefs.get("keyword.enabled") &&
-          (UrlbarTokenizer.looksLikeOrigin(str, {
-            noIp: true,
-            noPort: true,
-          }) ||
-            UrlbarTokenizer.REGEXP_COMMON_EMAIL.test(str))
-        ) {
-          let searchResult = await this._defaultEngineSearchResult(
-            queryContext
-          );
-          if (!this.queries.has(queryContext)) {
-            return;
-          }
-          addCallback(this, searchResult);
-        }
-      }
-    } else {
-      result = await this._defaultEngineSearchResult(queryContext);
-      if (!result || !this.queries.has(queryContext)) {
-        return;
-      }
-      result.heuristic = true;
-      addCallback(this, result);
-    }
-
-    this.queries.delete(queryContext);
-  }
-
-  /**
-   * Cancels a running query.
-   * @param {object} queryContext The query context object
-   */
-  cancelQuery(queryContext) {
-    logger.info(`Canceling query for ${queryContext.searchString}`);
-    this.queries.delete(queryContext);
-  }
-
-  // TODO (bug 1054814): Use visited URLs to inform which scheme to use, if the
-  // scheme isn't specificed.
-  _matchUnknownUrl(queryContext) {
-    let unescapedSearchString = Services.textToSubURI.unEscapeURIForUI(
-      queryContext.searchString
-    );
-    let [prefix, suffix] = UrlbarUtils.stripURLPrefix(unescapedSearchString);
-    if (!suffix && prefix) {
-      // The user just typed a stripped protocol, don't build a non-sense url
-      // like http://http/ for it.
-      return null;
-    }
-    // The user may have typed something like "word?" to run a search, we should
-    // not convert that to a url.
-    if (
-      queryContext.restrictSource &&
-      queryContext.restrictSource == UrlbarUtils.RESULT_SOURCE.SEARCH
-    ) {
-      return null;
-    }
-
-    let searchUrl = queryContext.searchString.trim();
-
-    if (queryContext.fixupError) {
-      if (
-        queryContext.fixupError == Cr.NS_ERROR_MALFORMED_URI &&
-        !UrlbarPrefs.get("keyword.enabled")
-      ) {
-        let result = new UrlbarResult(
-          UrlbarUtils.RESULT_TYPE.URL,
-          UrlbarUtils.RESULT_SOURCE.OTHER_LOCAL,
-          ...UrlbarResult.payloadAndSimpleHighlights(queryContext.tokens, {
-            title: [searchUrl, UrlbarUtils.HIGHLIGHT.TYPED],
-            url: [searchUrl, UrlbarUtils.HIGHLIGHT.TYPED],
-            icon: "",
-          })
-        );
-        result.heuristic = true;
-        return result;
-      }
-
-      return null;
-    }
-
-    // If the URI cannot be fixed or the preferred URI would do a keyword search,
-    // that basically means this isn't useful to us. Note that
-    // fixupInfo.keywordAsSent will never be true if the keyword.enabled pref
-    // is false or there are no engines, so in that case we will always return
-    // a "visit".
-    if (!queryContext.fixupInfo?.href || queryContext.fixupInfo?.isSearch) {
-      return null;
-    }
-
-    let uri = new URL(queryContext.fixupInfo.href);
-    // Check the host, as "http:///" is a valid nsIURI, but not useful to us.
-    // But, some schemes are expected to have no host. So we check just against
-    // schemes we know should have a host. This allows new schemes to be
-    // implemented without us accidentally blocking access to them.
-    let hostExpected = ["http:", "https:", "ftp:", "chrome:"].includes(
-      uri.protocol
-    );
-    if (hostExpected && !uri.host) {
-      return null;
-    }
-
-    // getFixupURIInfo() escaped the URI, so it may not be pretty.  Embed the
-    // escaped URL in the result since that URL should be "canonical".  But
-    // pass the pretty, unescaped URL as the result's title, since it is
-    // displayed to the user.
-    let escapedURL = uri.toString();
-    let displayURL = decodeURI(uri);
-
-    // We don't know if this url is in Places or not, and checking that would
-    // be expensive. Thus we also don't know if we may have an icon.
-    // If we'd just try to fetch the icon for the typed string, we'd cause icon
-    // flicker, since the url keeps changing while the user types.
-    // By default we won't provide an icon, but for the subset of urls with a
-    // host we'll check for a typed slash and set favicon for the host part.
-    let iconUri = "";
-    if (hostExpected && (searchUrl.endsWith("/") || uri.pathname.length > 1)) {
-      // Look for an icon with the entire URL except for the pathname, including
-      // scheme, usernames, passwords, hostname, and port.
-      let pathIndex = uri.toString().lastIndexOf(uri.pathname);
-      let prePath = uri.toString().slice(0, pathIndex);
-      iconUri = `page-icon:${prePath}/`;
-    }
-
-    let result = new UrlbarResult(
-      UrlbarUtils.RESULT_TYPE.URL,
-      UrlbarUtils.RESULT_SOURCE.OTHER_LOCAL,
-      ...UrlbarResult.payloadAndSimpleHighlights(queryContext.tokens, {
-        title: [displayURL, UrlbarUtils.HIGHLIGHT.TYPED],
-        url: [escapedURL, UrlbarUtils.HIGHLIGHT.TYPED],
-        icon: iconUri,
-      })
-    );
-    result.heuristic = true;
-    return result;
-  }
-
-  async _defaultEngineSearchResult(queryContext) {
-    let engine;
-    if (queryContext.engineName) {
-      engine = Services.search.getEngineByName(queryContext.engineName);
-    } else if (queryContext.isPrivate) {
-      engine = Services.search.defaultPrivateEngine;
-    } else {
-      engine = Services.search.defaultEngine;
-    }
-
-    if (!engine) {
-      return null;
-    }
-
-    // Strip a leading search restriction char, because we prepend it to text
-    // when the search shortcut is used and it's not user typed. Don't strip
-    // other restriction chars, so that it's possible to search for things
-    // including one of those (e.g. "c#").
-    let query = queryContext.searchString;
-    if (
-      queryContext.tokens[0] &&
-      queryContext.tokens[0].value === UrlbarTokenizer.RESTRICT.SEARCH
-    ) {
-      query = UrlbarUtils.substringAfter(
-        query,
-        queryContext.tokens[0].value
-      ).trim();
-    }
-
-    let result = new UrlbarResult(
-      UrlbarUtils.RESULT_TYPE.SEARCH,
-      UrlbarUtils.RESULT_SOURCE.SEARCH,
-      ...UrlbarResult.payloadAndSimpleHighlights(queryContext.tokens, {
-        engine: [engine.name, UrlbarUtils.HIGHLIGHT.TYPED],
-        icon: [engine.iconURI?.spec || ""],
-        query: [query, UrlbarUtils.HIGHLIGHT.NONE],
-        // We're confident that there is no alias, since UnifiedComplete
-        // handles heuristic searches with aliases.
-        keyword: undefined,
-        keywordOffer: UrlbarUtils.KEYWORD_OFFER.NONE,
-        // For test interoperabilty with UrlbarProviderSearchSuggestions.
-        suggestion: undefined,
-        tailPrefix: undefined,
-        tail: undefined,
-        tailOffsetIndex: -1,
-        isSearchHistory: false,
-      })
-    );
-    return result;
-  }
-}
-
-var UrlbarProviderHeuristicFallback = new ProviderHeuristicFallback();
diff --git a/browser/components/urlbar/UrlbarProviderOmnibox.jsm b/browser/components/urlbar/UrlbarProviderOmnibox.jsm
index 0ae009353dd41..795e60e511a23 100644
--- a/browser/components/urlbar/UrlbarProviderOmnibox.jsm
+++ b/browser/components/urlbar/UrlbarProviderOmnibox.jsm
@@ -55,7 +55,7 @@ class ProviderOmnibox extends UrlbarProvider {
    * @returns {integer} one of the types from UrlbarUtils.PROVIDER_TYPE.*
    */
   get type() {
-    return UrlbarUtils.PROVIDER_TYPE.HEURISTIC;
+    return UrlbarUtils.PROVIDER_TYPE.EXTENSION;
   }
 
   /**
@@ -120,25 +120,8 @@ class ProviderOmnibox extends UrlbarProvider {
     let instance = {};
     this.queries.set(queryContext, instance);
 
-    // Fetch heuristic result.
-    let keyword = queryContext.tokens[0].value;
-    let description = ExtensionSearchHandler.getDescription(keyword);
-    let heuristicResult = new UrlbarResult(
-      UrlbarUtils.RESULT_TYPE.OMNIBOX,
-      UrlbarUtils.RESULT_SOURCE.OTHER_NETWORK,
-      ...UrlbarResult.payloadAndSimpleHighlights(queryContext.tokens, {
-        title: [description, UrlbarUtils.HIGHLIGHT.TYPED],
-        content: [queryContext.searchString, UrlbarUtils.HIGHLIGHT.TYPED],
-        keyword: [queryContext.tokens[0].value, UrlbarUtils.HIGHLIGHT.TYPED],
-        icon: UrlbarUtils.ICON.EXTENSION,
-      })
-    );
-    heuristicResult.heuristic = true;
-    addCallback(this, heuristicResult);
-
-    // Fetch non-heuristic results.
     let data = {
-      keyword,
+      keyword: queryContext.tokens[0].value,
       text: queryContext.searchString,
       inPrivateWindow: queryContext.isPrivate,
     };
@@ -147,9 +130,6 @@ class ProviderOmnibox extends UrlbarProvider {
       suggestions => {
         for (let suggestion of suggestions) {
           let content = `${queryContext.tokens[0].value} ${suggestion.content}`;
-          if (content == heuristicResult.payload.content) {
-            continue;
-          }
           let result = new UrlbarResult(
             UrlbarUtils.RESULT_TYPE.OMNIBOX,
             UrlbarUtils.RESULT_SOURCE.OTHER_NETWORK,
diff --git a/browser/components/urlbar/UrlbarProviderSearchSuggestions.jsm b/browser/components/urlbar/UrlbarProviderSearchSuggestions.jsm
index 788e60de0813a..0301a6bfd6d91 100644
--- a/browser/components/urlbar/UrlbarProviderSearchSuggestions.jsm
+++ b/browser/components/urlbar/UrlbarProviderSearchSuggestions.jsm
@@ -199,7 +199,10 @@ class ProviderSearchSuggestions extends UrlbarProvider {
 
     // Disallow remote suggestions for strings containing tokens that look like
     // URIs, to avoid disclosing information about networks or passwords.
-    if (queryContext.fixupInfo?.href && !queryContext.fixupInfo?.isSearch) {
+    if (
+      queryContext.fixupInfo.fixedURI &&
+      !queryContext.fixupInfo.keywordAsSent
+    ) {
       return false;
     }
 
diff --git a/browser/components/urlbar/UrlbarProviderUnifiedComplete.jsm b/browser/components/urlbar/UrlbarProviderUnifiedComplete.jsm
index 691cbe46b5c82..b980a164ce32f 100644
--- a/browser/components/urlbar/UrlbarProviderUnifiedComplete.jsm
+++ b/browser/components/urlbar/UrlbarProviderUnifiedComplete.jsm
@@ -90,17 +90,8 @@ class ProviderUnifiedComplete extends UrlbarProvider {
         acResult,
         urls
       );
-      // The Muxer gives UnifiedComplete special status and waits for it to
-      // return results before sorting them. We need to know that
-      // UnifiedComplete has finished even if it isn't returning results, so we
-      // call addCallback with an empty result here, which is something only
-      // UnifiedComplete is allowed to do.
-      if (!results.length) {
-        addCallback(this, null);
-      } else {
-        for (let result of results) {
-          addCallback(this, result);
-        }
+      for (let result of results) {
+        addCallback(this, result);
       }
     });
     this.queries.delete(queryContext);
@@ -263,6 +254,17 @@ function makeUrlbarResult(tokens, info) {
           })
         );
       }
+      case "extension":
+        return new UrlbarResult(
+          UrlbarUtils.RESULT_TYPE.OMNIBOX,
+          UrlbarUtils.RESULT_SOURCE.OTHER_NETWORK,
+          ...UrlbarResult.payloadAndSimpleHighlights(tokens, {
+            title: [info.comment, UrlbarUtils.HIGHLIGHT.TYPED],
+            content: [action.params.content, UrlbarUtils.HIGHLIGHT.TYPED],
+            keyword: [action.params.keyword, UrlbarUtils.HIGHLIGHT.TYPED],
+            icon: [info.icon],
+          })
+        );
       case "remotetab":
         return new UrlbarResult(
           UrlbarUtils.RESULT_TYPE.REMOTE_TAB,
diff --git a/browser/components/urlbar/UrlbarProvidersManager.jsm b/browser/components/urlbar/UrlbarProvidersManager.jsm
index 4c607647f1b3d..1a0a2c0850527 100644
--- a/browser/components/urlbar/UrlbarProvidersManager.jsm
+++ b/browser/components/urlbar/UrlbarProvidersManager.jsm
@@ -35,8 +35,6 @@ XPCOMUtils.defineLazyGetter(this, "logger", () =>
 var localProviderModules = {
   UrlbarProviderUnifiedComplete:
     "resource:///modules/UrlbarProviderUnifiedComplete.jsm",
-  UrlbarProviderHeuristicFallback:
-    "resource:///modules/UrlbarProviderHeuristicFallback.jsm",
   UrlbarProviderInterventions:
     "resource:///modules/UrlbarProviderInterventions.jsm",
   UrlbarProviderOmnibox: "resource:///modules/UrlbarProviderOmnibox.jsm",
@@ -366,7 +364,6 @@ class Query {
     let queryPromises = [];
     for (let provider of activeProviders) {
       if (provider.type == UrlbarUtils.PROVIDER_TYPE.HEURISTIC) {
-        this.context.pendingHeuristicProviders.add(provider.name);
         queryPromises.push(
           provider.tryMethod("startQuery", this.context, this.add.bind(this))
         );
@@ -437,29 +434,13 @@ class Query {
     if (!(provider instanceof UrlbarProvider)) {
       throw new Error("Invalid provider passed to the add callback");
     }
-
-    // When this set is empty, we can display heuristic results early. We remove
-    // the provider from the list without checking result.heuristic since
-    // heuristic providers don't necessarily have to return heuristic results.
-    // We expect a provider with type HEURISTIC will return its heuristic
-    // result(s) first.
-    this.context.pendingHeuristicProviders.delete(provider.name);
-
     // Stop returning results as soon as we've been canceled.
     if (this.canceled) {
       return;
     }
-
-    let addResult = true;
-
-    if (!result) {
-      addResult = false;
-    }
-
     // Check if the result source should be filtered out. Pay attention to the
     // heuristic result though, that is supposed to be added regardless.
     if (
-      addResult &&
       !this.acceptableSources.includes(result.source) &&
       !result.heuristic &&
       // Treat form history as searches for the purpose of acceptableSources.
@@ -467,60 +448,35 @@ class Query {
         result.source != UrlbarUtils.RESULT_SOURCE.HISTORY ||
         !this.acceptableSources.includes(UrlbarUtils.RESULT_SOURCE.SEARCH))
     ) {
-      addResult = false;
+      return;
     }
 
     // Filter out javascript results for safety. The provider is supposed to do
     // it, but we don't want to risk leaking these out.
     if (
-      addResult &&
       result.type != UrlbarUtils.RESULT_TYPE.KEYWORD &&
       result.payload.url &&
       result.payload.url.startsWith("javascript:") &&
       !this.context.searchString.startsWith("javascript:") &&
       UrlbarPrefs.get("filter.javascript")
     ) {
-      addResult = false;
-    }
-
-    // We wait on UnifiedComplete to return a heuristic result. If it has no
-    // heuristic result to return, we still need to sort and display results, so
-    // we follow the usual codepath to muxer.sort. We only offer this for
-    // UnifiedComplete, so we check the provider's name here. This is a stopgap
-    // measure until bug 1648468 lands.
-    if (!addResult) {
-      if (provider.name == "UnifiedComplete") {
-        this._notifyResultsFromProvider(provider);
-      }
       return;
     }
+
     result.providerName = provider.name;
-    result.providerType = provider.type;
     this.context.results.push(result);
     if (result.heuristic) {
-      this.context.allHeuristicResults.push(result);
+      this.context.heuristicResult = result;
     }
 
     this._notifyResultsFromProvider(provider);
   }
 
   _notifyResultsFromProvider(provider) {
-    // We create two chunking timers: one for heuristic results, and one for
-    // other results. We expect heuristic providers to return their heuristic
-    // results before other results/providers in most cases. When all heuristic
-    // providers have returned some results, we fire the heuristic timer early.
-    // If the timer fires first, we stop waiting on the remaining heuristic
-    // providers.
-    // Both timers are used to reduce UI flicker.
+    // If the provider is not of heuristic type, chunk results, to improve the
+    // dataflow and reduce UI flicker.
     if (provider.type == UrlbarUtils.PROVIDER_TYPE.HEURISTIC) {
-      if (!this._heuristicProviderTimer) {
-        this._heuristicProviderTimer = new SkippableTimer({
-          name: "Heuristic provider timer",
-          callback: () => this._notifyResults(),
-          time: CHUNK_RESULTS_DELAY_MS,
-          logger,
-        });
-      }
+      this._notifyResults();
     } else if (!this._chunkTimer) {
       this._chunkTimer = new SkippableTimer({
         name: "Query chunk timer",
@@ -529,33 +485,16 @@ class Query {
         logger,
       });
     }
-    // If all active heuristic providers have returned results, we can skip the
-    // heuristic results timer and start showing results immediately.
-    if (
-      this._heuristicProviderTimer &&
-      !this.context.pendingHeuristicProviders.size
-    ) {
-      this._heuristicProviderTimer.fire().catch(Cu.reportError);
-    }
   }
 
   _notifyResults() {
-    let sorted = this.muxer.sort(this.context);
-
-    if (this._heuristicProviderTimer) {
-      this._heuristicProviderTimer.cancel().catch(Cu.reportError);
-      this._heuristicProviderTimer = null;
-    }
+    this.muxer.sort(this.context);
 
     if (this._chunkTimer) {
       this._chunkTimer.cancel().catch(Cu.reportError);
       this._chunkTimer = null;
     }
 
-    if (!sorted) {
-      return;
-    }
-
     // Before the muxer.sort call above, this.context.results should never be
     // empty since this method is called when results are added.  But the muxer
     // may have excluded one or more results from the final sorted list.  For
diff --git a/browser/components/urlbar/UrlbarUtils.jsm b/browser/components/urlbar/UrlbarUtils.jsm
index 4094083696442..d521e0407e140 100644
--- a/browser/components/urlbar/UrlbarUtils.jsm
+++ b/browser/components/urlbar/UrlbarUtils.jsm
@@ -607,28 +607,6 @@ var UrlbarUtils = {
     return index < 0 ? "" : sourceStr.substr(index + targetStr.length);
   },
 
-  /**
-   * Strips the prefix from a URL and returns the prefix and the remainder of the
-   * URL.  "Prefix" is defined to be the scheme and colon, plus, if present, two
-   * slashes.  If the given string is not actually a URL, then an empty prefix and
-   * the string itself is returned.
-   *
-   * @param {string} str The possible URL to strip.
-   * @returns {array} If `str` is a URL, then [prefix, remainder].  Otherwise, ["", str].
-   */
-  stripURLPrefix(str) {
-    const REGEXP_STRIP_PREFIX = /^[a-z]+:(?:\/){0,2}/i;
-    let match = REGEXP_STRIP_PREFIX.exec(str);
-    if (!match) {
-      return ["", str];
-    }
-    let prefix = match[0];
-    if (prefix.length < str.length && str[prefix.length] == " ") {
-      return ["", str];
-    }
-    return [prefix, str.substr(prefix.length)];
-  },
-
   /**
    * Runs a search for the given string, and returns the heuristic result.
    * @param {string} searchString The string to search for.
@@ -651,7 +629,7 @@ var UrlbarUtils = {
         "usercontextid"
       ),
       allowSearchSuggestions: false,
-      providers: ["UnifiedComplete", "HeuristicFallback"],
+      providers: ["UnifiedComplete"],
     });
     await UrlbarProvidersManager.startQuery(context);
     if (!context.heuristicResult) {
@@ -1000,8 +978,6 @@ class UrlbarQueryContext {
     }
 
     this.lastResultCount = 0;
-    this.allHeuristicResults = [];
-    this.pendingHeuristicProviders = new Set();
     this.userContextId =
       options.userContextId ||
       Ci.nsIScriptSecurityManager.DEFAULT_USER_CONTEXT_ID;
@@ -1027,12 +1003,9 @@ class UrlbarQueryContext {
 
   /**
    * Caches and returns fixup info from URIFixup for the current search string.
-   * Only returns a subset of the properties from URIFixup. This is both to
-   * reduce the memory footprint of UrlbarQueryContexts and to keep them
-   * serializable so they can be sent to extensions.
    */
   get fixupInfo() {
-    if (this.searchString.trim() && !this._fixupInfo) {
+    if (this.searchString && !this._fixupInfo) {
       let flags =
         Ci.nsIURIFixup.FIXUP_FLAG_FIX_SCHEME_TYPOS |
         Ci.nsIURIFixup.FIXUP_FLAG_ALLOW_KEYWORD_LOOKUP;
@@ -1040,35 +1013,14 @@ class UrlbarQueryContext {
         flags |= Ci.nsIURIFixup.FIXUP_FLAG_PRIVATE_CONTEXT;
       }
 
-      try {
-        let info = Services.uriFixup.getFixupURIInfo(
-          this.searchString.trim(),
-          flags
-        );
-        this._fixupInfo = {
-          href: info.fixedURI.spec,
-          isSearch: !!info.keywordAsSent,
-        };
-      } catch (ex) {
-        this._fixupError = ex.result;
-      }
+      this._fixupInfo = Services.uriFixup.getFixupURIInfo(
+        this.searchString.trim(),
+        flags
+      );
     }
 
     return this._fixupInfo || null;
   }
-
-  /**
-   * Returns the error that was thrown when fixupInfo was fetched, if any. If
-   * fixupInfo has not yet been fetched for this queryContext, it is fetched
-   * here.
-   */
-  get fixupError() {
-    if (!this.fixupInfo) {
-      return this._fixupError;
-    }
-
-    return null;
-  }
 }
 
 /**
diff --git a/browser/components/urlbar/moz.build b/browser/components/urlbar/moz.build
index 556eb701a1e4a..e06e4157d3944 100644
--- a/browser/components/urlbar/moz.build
+++ b/browser/components/urlbar/moz.build
@@ -12,7 +12,6 @@ EXTRA_JS_MODULES += [
     'UrlbarMuxerUnifiedComplete.jsm',
     'UrlbarPrefs.jsm',
     'UrlbarProviderExtension.jsm',
-    'UrlbarProviderHeuristicFallback.jsm',
     'UrlbarProviderInterventions.jsm',
     'UrlbarProviderOmnibox.jsm',
     'UrlbarProviderOpenTabs.jsm',
diff --git a/browser/components/urlbar/tests/UrlbarTestUtils.jsm b/browser/components/urlbar/tests/UrlbarTestUtils.jsm
index 016b6cca4dd9e..617dc4e76271a 100644
--- a/browser/components/urlbar/tests/UrlbarTestUtils.jsm
+++ b/browser/components/urlbar/tests/UrlbarTestUtils.jsm
@@ -598,7 +598,7 @@ class TestProvider extends UrlbarProvider {
    */
   constructor({
     results,
-    name = Math.floor(Math.random() * 100000),
+    name = "TestProvider" + Math.floor(Math.random() * 100000),
     type = UrlbarUtils.PROVIDER_TYPE.PROFILE,
     priority = 0,
     addTimeout = 0,
@@ -613,7 +613,7 @@ class TestProvider extends UrlbarProvider {
     this._onCancel = onCancel;
   }
   get name() {
-    return "TestProvider" + this._name;
+    return this._name;
   }
   get type() {
     return this._type;
diff --git a/browser/components/urlbar/tests/browser/browser_updateRows.js b/browser/components/urlbar/tests/browser/browser_updateRows.js
index b764c166bf6d9..b1d6e983c7af5 100644
--- a/browser/components/urlbar/tests/browser/browser_updateRows.js
+++ b/browser/components/urlbar/tests/browser/browser_updateRows.js
@@ -21,19 +21,19 @@ add_task(async function urlToTip() {
   ]);
 
   // Add a provider that returns a tip result when the search string is "testx".
-  let tipResult = new UrlbarResult(
-    UrlbarUtils.RESULT_TYPE.TIP,
-    UrlbarUtils.RESULT_SOURCE.OTHER_LOCAL,
-    {
-      text: "This is a test tip.",
-      buttonText: "OK",
-      helpUrl: "http://example.com/",
-      type: "test",
-    }
-  );
-  tipResult.suggestedIndex = 1;
   let provider = new UrlbarTestUtils.TestProvider({
-    results: [tipResult],
+    results: [
+      new UrlbarResult(
+        UrlbarUtils.RESULT_TYPE.TIP,
+        UrlbarUtils.RESULT_SOURCE.OTHER_LOCAL,
+        {
+          text: "This is a test tip.",
+          buttonText: "OK",
+          helpUrl: "http://example.com/",
+          type: "test",
+        }
+      ),
+    ],
   });
   provider.isActive = context => context.searchString == "testx";
   UrlbarProvidersManager.registerProvider(provider);
@@ -122,19 +122,19 @@ add_task(async function tipToURL() {
 
   // Add a provider that returns a tip result when the search string is "test"
   // or "testxx".
-  let tipResult = new UrlbarResult(
-    UrlbarUtils.RESULT_TYPE.TIP,
-    UrlbarUtils.RESULT_SOURCE.OTHER_LOCAL,
-    {
-      text: "This is a test tip.",
-      buttonText: "OK",
-      helpUrl: "http://example.com/",
-      type: "test",
-    }
-  );
-  tipResult.suggestedIndex = 1;
   let provider = new UrlbarTestUtils.TestProvider({
-    results: [tipResult],
+    results: [
+      new UrlbarResult(
+        UrlbarUtils.RESULT_TYPE.TIP,
+        UrlbarUtils.RESULT_SOURCE.OTHER_LOCAL,
+        {
+          text: "This is a test tip.",
+          buttonText: "OK",
+          helpUrl: "http://example.com/",
+          type: "test",
+        }
+      ),
+    ],
   });
   provider.isActive = context =>
     ["test", "testxx"].includes(context.searchString);
diff --git a/browser/components/urlbar/tests/unit/test_providerHeuristicFallback.js b/browser/components/urlbar/tests/unit/test_providerHeuristicFallback.js
deleted file mode 100644
index 9dd9c02a501b0..0000000000000
--- a/browser/components/urlbar/tests/unit/test_providerHeuristicFallback.js
+++ /dev/null
@@ -1,536 +0,0 @@
-/* Any copyright is dedicated to the Public Domain.
-   http://creativecommons.org/publicdomain/zero/1.0/ */
-
-/**
- * Tests that visit-url and search engine heuristic results are returned by
- * UrlbarProviderHeuristicFallback.
- */
-
-const ENGINE_NAME = "engine-suggestions.xml";
-const SUGGEST_PREF = "browser.urlbar.suggest.searches";
-const SUGGEST_ENABLED_PREF = "browser.search.suggest.enabled";
-const PRIVATE_SEARCH_PREF = "browser.search.separatePrivateDefault.ui.enabled";
-
-add_task(async function setup() {
-  // Install a test engine so we're sure of ENGINE_NAME.
-  let engine = await addTestSuggestionsEngine();
-
-  // Install the test engine.
-  let oldDefaultEngine = await Services.search.getDefault();
-  registerCleanupFunction(async () => {
-    Services.search.setDefault(oldDefaultEngine);
-    Services.prefs.clearUserPref(SUGGEST_PREF);
-    Services.prefs.clearUserPref(SUGGEST_ENABLED_PREF);
-    Services.prefs.clearUserPref(PRIVATE_SEARCH_PREF);
-  });
-  Services.search.setDefault(engine);
-  Services.prefs.setBoolPref(SUGGEST_PREF, false);
-  Services.prefs.setBoolPref(SUGGEST_ENABLED_PREF, false);
-  Services.prefs.setBoolPref(PRIVATE_SEARCH_PREF, false);
-});
-
-add_task(async function() {
-  info("visit url, no protocol");
-  let query = "mozilla.org";
-  let context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `http://${query}/`,
-        title: `http://${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-      makeSearchResult(context, {
-        engineName: ENGINE_NAME,
-      }),
-    ],
-  });
-
-  info("visit url, no protocol but with 2 dots");
-  query = "www.mozilla.org";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `http://${query}/`,
-        title: `http://${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-      makeSearchResult(context, {
-        engineName: ENGINE_NAME,
-      }),
-    ],
-  });
-
-  info("visit url, no protocol, e-mail like");
-  query = "a@b.com";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `http://${query}/`,
-        title: `http://${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-      makeSearchResult(context, {
-        engineName: ENGINE_NAME,
-      }),
-    ],
-  });
-
-  info("visit url, with protocol but with 2 dots");
-  query = "https://www.mozilla.org";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `${query}/`,
-        title: `${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  // info("visit url, with protocol but with 3 dots");
-  query = "https://www.mozilla.org.tw";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `${query}/`,
-        title: `${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("visit url, with protocol");
-  query = "https://mozilla.org";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `${query}/`,
-        title: `${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("visit url, about: protocol (no host)");
-  query = "about:nonexistent";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: query,
-        title: query,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("visit url, with non-standard whitespace");
-  query = "https://mozilla.org";
-  context = createContext(`${query}\u2028`, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `${query}/`,
-        title: `${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  // This is distinct because of how we predict being able to url autofill via
-  // host lookups.
-  info("visit url, host matching visited host but not visited url");
-  await PlacesTestUtils.addVisits([
-    {
-      uri: Services.io.newURI("http://mozilla.org/wine/"),
-      title: "Mozilla Wine",
-      transition: PlacesUtils.history.TRANSITION_TYPED,
-    },
-  ]);
-  query = "mozilla.org/rum";
-  context = createContext(`${query}\u2028`, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `http://${query}`,
-        title: `http://${query}`,
-        iconUri: "page-icon:http://mozilla.org/",
-        heuristic: true,
-      }),
-    ],
-  });
-  await PlacesUtils.history.clear();
-
-  // And hosts with no dot in them are special, due to requiring safelisting.
-  info("unknown host");
-  query = "firefox";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeSearchResult(context, {
-        engineName: ENGINE_NAME,
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("string with known host");
-  Services.prefs.setBoolPref("browser.fixup.defaultToSearch", true);
-  query = "firefox/get";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeSearchResult(context, {
-        engineName: ENGINE_NAME,
-        heuristic: true,
-      }),
-    ],
-  });
-
-  Services.prefs.setBoolPref("browser.fixup.defaultToSearch", false);
-  query = "firefox/get";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `http://${query}`,
-        title: `http://${query}`,
-        iconUri: "page-icon:http://firefox/",
-        heuristic: true,
-      }),
-    ],
-  });
-  Services.prefs.clearUserPref("browser.fixup.defaultToSearch");
-
-  Services.prefs.setBoolPref("browser.fixup.domainwhitelist.firefox", true);
-  registerCleanupFunction(() => {
-    Services.prefs.clearUserPref("browser.fixup.domainwhitelist.firefox");
-  });
-
-  info("known host");
-  query = "firefox";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `http://${query}/`,
-        title: `http://${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-      makeSearchResult(context, {
-        engineName: ENGINE_NAME,
-      }),
-    ],
-  });
-
-  info("url with known host");
-  query = "firefox/get";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `http://${query}`,
-        title: `http://${query}`,
-        iconUri: "page-icon:http://firefox/",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("visit url, host matching visited host but not visited url, known host");
-  Services.prefs.setBoolPref("browser.fixup.domainwhitelist.mozilla", true);
-  registerCleanupFunction(() => {
-    Services.prefs.clearUserPref("browser.fixup.domainwhitelist.mozilla");
-  });
-  query = "mozilla/rum";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `http://${query}`,
-        title: `http://${query}`,
-        iconUri: "page-icon:http://mozilla/",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  // ipv4 and ipv6 literal addresses should offer to visit.
-  info("visit url, ipv4 literal");
-  query = "127.0.0.1";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `http://${query}/`,
-        title: `http://${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("visit url, ipv6 literal");
-  query = "[2001:db8::1]";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `http://${query}/`,
-        title: `http://${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  // Setting keyword.enabled to false should always try to visit.
-  let keywordEnabled = Services.prefs.getBoolPref("keyword.enabled");
-  Services.prefs.setBoolPref("keyword.enabled", false);
-  registerCleanupFunction(() => {
-    Services.prefs.clearUserPref("keyword.enabled");
-  });
-  info("visit url, keyword.enabled = false");
-  query = "bacon";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `http://${query}/`,
-        title: `http://${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("visit two word query, keyword.enabled = false");
-  query = "bacon lovers";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: query,
-        title: query,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-  Services.prefs.setBoolPref("keyword.enabled", true);
-  info("visit two word query, keyword.enabled = true");
-  query = "bacon lovers";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeSearchResult(context, {
-        engineName: ENGINE_NAME,
-        heuristic: true,
-      }),
-    ],
-  });
-
-  Services.prefs.setBoolPref("keyword.enabled", keywordEnabled);
-
-  info("visit url, scheme+host");
-  query = "http://example";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `${query}/`,
-        title: `${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("visit url, scheme+host");
-  query = "ftp://example";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `${query}/`,
-        title: `${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("visit url, host+port");
-  query = "example:8080";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: `http://${query}/`,
-        title: `http://${query}/`,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("numerical operations that look like urls should search");
-  query = "123/12";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeSearchResult(context, {
-        engineName: ENGINE_NAME,
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("numerical operations that look like urls should search");
-  query = "123.12/12.1";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeSearchResult(context, {
-        engineName: ENGINE_NAME,
-        heuristic: true,
-      }),
-    ],
-  });
-
-  query = "resource:///modules";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: query,
-        title: query,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("access resource://app/modules");
-  query = "resource://app/modules";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeVisitResult(context, {
-        uri: query,
-        title: query,
-        iconUri: "",
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("protocol with an extra slash");
-  query = "http:///";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeSearchResult(context, {
-        engineName: ENGINE_NAME,
-        heuristic: true,
-      }),
-    ],
-  });
-
-  info("change default engine");
-  let originalTestEngine = Services.search.getEngineByName(ENGINE_NAME);
-  let engine2 = await Services.search.addEngineWithDetails("AliasEngine", {
-    alias: "alias",
-    method: "GET",
-    template: "http://example.com/?q={searchTerms}",
-  });
-  Assert.notEqual(
-    Services.search.defaultEngine,
-    engine2,
-    "New engine shouldn't be the current engine yet"
-  );
-  await Services.search.setDefault(engine2);
-  query = "toronto";
-  context = createContext(query, { isPrivate: false });
-  await check_results({
-    context,
-    matches: [
-      makeSearchResult(context, {
-        engineName: "AliasEngine",
-        heuristic: true,
-      }),
-    ],
-  });
-  await Services.search.setDefault(originalTestEngine);
-
-  info(
-    "Leading restriction tokens are not removed from the search result, apart from the search token."
-  );
-  // Note that we use the alias from AliasEngine in the query. Since we're using
-  // a restriction token, we expect that the default engine be used.
-  for (let token of Object.values(UrlbarTokenizer.RESTRICT)) {
-    for (query of [`${token} alias query`, `query ${token}`]) {
-      let expectedQuery =
-        token == UrlbarTokenizer.RESTRICT.SEARCH &&
-        query.startsWith(UrlbarTokenizer.RESTRICT.SEARCH)
-          ? query.substring(2)
-          : query;
-      context = createContext(query, { isPrivate: false });
-      info(`Searching for "${query}", expecting "${expectedQuery}"`);
-      await check_results({
-        context,
-        matches: [
-          makeSearchResult(context, {
-            engineName: ENGINE_NAME,
-            query: expectedQuery,
-            heuristic: true,
-          }),
-        ],
-      });
-    }
-  }
-  await Services.search.removeEngine(engine2);
-});
diff --git a/browser/components/urlbar/tests/unit/test_providersManager_filtering.js b/browser/components/urlbar/tests/unit/test_providersManager_filtering.js
index cd4ccf72e16cf..cfe4a9cb674ea 100644
--- a/browser/components/urlbar/tests/unit/test_providersManager_filtering.js
+++ b/browser/components/urlbar/tests/unit/test_providersManager_filtering.js
@@ -359,16 +359,30 @@ add_task(async function test_filter_priority() {
   /**
    * A test provider.
    */
-  class TestProvider extends UrlbarTestUtils.TestProvider {
+  class TestProvider extends UrlbarProvider {
     constructor(priority, shouldBeInvoked, namePart = "") {
       super();
       this._priority = priority;
-      this._name = `${priority}` + namePart;
+      this._name = `Provider-${priority}` + namePart;
       this._shouldBeInvoked = shouldBeInvoked;
     }
+    get name() {
+      return this._name;
+    }
+    get type() {
+      return UrlbarUtils.PROVIDER_TYPE.PROFILE;
+    }
+    isActive(context) {
+      return true;
+    }
+    getPriority(context) {
+      return this._priority;
+    }
     async startQuery(context, add) {
       Assert.ok(this._shouldBeInvoked, `${this.name} was invoked`);
     }
+    cancelQuery(context) {}
+    pickResult(result) {}
   }
 
   // Test all possible orderings of the providers to make sure the logic that
diff --git a/browser/components/urlbar/tests/unit/xpcshell.ini b/browser/components/urlbar/tests/unit/xpcshell.ini
index d9b6a3f349664..2f006f89b0f55 100644
--- a/browser/components/urlbar/tests/unit/xpcshell.ini
+++ b/browser/components/urlbar/tests/unit/xpcshell.ini
@@ -6,7 +6,6 @@ support-files =
   data/engine-tail-suggestions.xml
 
 [test_muxer.js]
-[test_providerHeuristicFallback.js]
 [test_providerOmnibox.js]
 [test_providerOpenTabs.js]
 [test_providersManager.js]
diff --git a/browser/modules/test/browser/browser_UsageTelemetry_urlbar_tip.js b/browser/modules/test/browser/browser_UsageTelemetry_urlbar_tip.js
index 4aef2c892abb6..331bb540449b1 100644
--- a/browser/modules/test/browser/browser_UsageTelemetry_urlbar_tip.js
+++ b/browser/modules/test/browser/browser_UsageTelemetry_urlbar_tip.js
@@ -122,7 +122,7 @@ class TipProvider extends UrlbarProvider {
     this._results = results;
   }
   get name() {
-    return "TestProviderTip";
+    return "TestTipProvider";
   }
   get type() {
     return UrlbarUtils.PROVIDER_TYPE.PROFILE;
diff --git a/toolkit/components/places/UnifiedComplete.jsm b/toolkit/components/places/UnifiedComplete.jsm
index 410b0d89fe877..7151c61a38d18 100644
--- a/toolkit/components/places/UnifiedComplete.jsm
+++ b/toolkit/components/places/UnifiedComplete.jsm
@@ -340,6 +340,7 @@ XPCOMUtils.defineLazyGlobalGetters(this, ["fetch"]);
 XPCOMUtils.defineLazyModuleGetters(this, {
   AboutPagesUtils: "resource://gre/modules/AboutPagesUtils.jsm",
   BrowserUtils: "resource://gre/modules/BrowserUtils.jsm",
+  ExtensionSearchHandler: "resource://gre/modules/ExtensionSearchHandler.jsm",
   ObjectUtils: "resource://gre/modules/ObjectUtils.jsm",
   PlacesRemoteTabsAutocompleteProvider:
     "resource://gre/modules/PlacesRemoteTabsAutocompleteProvider.jsm",
@@ -759,9 +760,9 @@ function Search(
     // actually the first thing in the search string.  If a prefix or restriction
     // character occurs first, then the heurstic token is null.  We use the
     // heuristic token to help determine the heuristic result.  It may be a Places
-    // keyword, a search engine alias, or simply a URL or part of the search
-    // string the user has typed.  We won't know until we create the heuristic
-    // result.
+    // keyword, a search engine alias, an extension keyword, or simply a URL or
+    // part of the search string the user has typed.  We won't know until we
+    // create the heuristic result.
     let firstToken = !!this._searchTokens.length && this._searchTokens[0].value;
     this._heuristicToken =
       firstToken && this._trimmedOriginalSearchString.startsWith(firstToken)
@@ -1271,6 +1272,16 @@ Search.prototype = {
     // We always try to make the first result a special "heuristic" result.  The
     // heuristics below determine what type of result it will be, if any.
 
+    if (this._heuristicToken) {
+      // It may be a keyword registered by an extension.
+      let matched = await this._matchExtensionHeuristicResult(
+        this._heuristicToken
+      );
+      if (matched) {
+        return true;
+      }
+    }
+
     if (this.pending && this._enableActions && this._heuristicToken) {
       // It may be a search engine with an alias - which works like a keyword.
       let matched = await this._matchSearchEngineAlias(this._heuristicToken);
@@ -1327,7 +1338,50 @@ Search.prototype = {
       }
     }
 
-    // Fall back to UrlbarProviderHeuristicFallback.
+    if (this.pending && this._searchTokens.length && this._enableActions) {
+      // If we don't have a result that matches what we know about, then
+      // we use a fallback for things we don't know about.
+
+      // We may not have auto-filled, but this may still look like a URL.
+      // However, even if the input is a valid URL, we may not want to use
+      // it as such. This can happen if the host isn't using a known TLD
+      // and hasn't been added to a user-controlled list of known domains,
+      // and/or if it looks like an email address.
+      let matched = await this._matchUnknownUrl();
+      if (matched) {
+        // Since we can't tell if this is a real URL and whether the user wants
+        // to visit or search for it, we provide an alternative searchengine
+        // match if the string looks like an alphanumeric origin or an e-mail.
+        let str = this._originalSearchString;
+        try {
+          new URL(str);
+        } catch (ex) {
+          if (
+            UrlbarPrefs.get("keyword.enabled") &&
+            (UrlbarTokenizer.looksLikeOrigin(str, {
+              noIp: true,
+              noPort: true,
+            }) ||
+              UrlbarTokenizer.REGEXP_COMMON_EMAIL.test(str))
+          ) {
+            this._addingHeuristicResult = false;
+            await this._matchCurrentSearchEngine();
+            this._addingHeuristicResult = true;
+          }
+        }
+        return true;
+      }
+    }
+
+    if (this.pending && this._enableActions && this._originalSearchString) {
+      // When all else fails, and the search string is non-empty, we search
+      // using the current search engine.
+      let matched = await this._matchCurrentSearchEngine();
+      if (matched) {
+        return true;
+      }
+    }
+
     return false;
   },
 
@@ -1358,6 +1412,18 @@ Search.prototype = {
     return gotResult;
   },
 
+  _matchExtensionHeuristicResult(keyword) {
+    if (
+      ExtensionSearchHandler.isKeywordRegistered(keyword) &&
+      substringAfter(this._originalSearchString, keyword)
+    ) {
+      let description = ExtensionSearchHandler.getDescription(keyword);
+      this._addExtensionMatch(this._originalSearchString, description);
+      return true;
+    }
+    return false;
+  },
+
   async _matchPlacesKeyword(keyword) {
     let entry = await PlacesUtils.keywords.fetch(keyword);
     if (!entry) {
@@ -1498,6 +1564,46 @@ Search.prototype = {
     return true;
   },
 
+  async _matchCurrentSearchEngine() {
+    let engine;
+    if (this._engineName) {
+      engine = Services.search.getEngineByName(this._engineName);
+    } else if (this._inPrivateWindow) {
+      engine = Services.search.defaultPrivateEngine;
+    } else {
+      engine = Services.search.defaultEngine;
+    }
+
+    if (!engine || !this.pending) {
+      return false;
+    }
+
+    // Strip a leading search restriction char, because we prepend it to text
+    // when the search shortcut is used and it's not user typed. Don't strip
+    // other restriction chars, so that it's possible to search for things
+    // including one of those (e.g. "c#").
+    let query = this._trimmedOriginalSearchString;
+    if (this._leadingRestrictionToken === UrlbarTokenizer.RESTRICT.SEARCH) {
+      query = substringAfter(query, this._leadingRestrictionToken).trim();
+    }
+    this._addSearchEngineMatch({ engine, query });
+    return true;
+  },
+
+  _addExtensionMatch(content, comment) {
+    this._addMatch({
+      value: makeActionUrl("extension", {
+        content,
+        keyword: this._heuristicToken,
+      }),
+      comment,
+      icon: "chrome://browser/content/extension.svg",
+      style: "action extension",
+      frecency: Infinity,
+      type: UrlbarUtils.RESULT_GROUP.EXTENSION,
+    });
+  },
+
   /**
    * Adds a search engine match.
    *
@@ -1597,6 +1703,106 @@ Search.prototype = {
     }
   },
 
+  // TODO (bug 1054814): Use visited URLs to inform which scheme to use, if the
+  // scheme isn't specificed.
+  _matchUnknownUrl() {
+    if (!this._searchString && this._strippedPrefix) {
+      // The user just typed a stripped protocol, don't build a non-sense url
+      // like http://http/ for it.
+      return false;
+    }
+    // The user may have typed something like "word?" to run a search, we should
+    // not convert that to a url.
+    if (this.hasBehavior("search") && this.hasBehavior("restrict")) {
+      return false;
+    }
+    let flags =
+      Ci.nsIURIFixup.FIXUP_FLAG_FIX_SCHEME_TYPOS |
+      Ci.nsIURIFixup.FIXUP_FLAG_ALLOW_KEYWORD_LOOKUP;
+    if (this._inPrivateWindow) {
+      flags |= Ci.nsIURIFixup.FIXUP_FLAG_PRIVATE_CONTEXT;
+    }
+    let fixupInfo = null;
+    let searchUrl = this._trimmedOriginalSearchString;
+    try {
+      fixupInfo = Services.uriFixup.getFixupURIInfo(searchUrl, flags);
+    } catch (e) {
+      if (
+        e.result == Cr.NS_ERROR_MALFORMED_URI &&
+        !UrlbarPrefs.get("keyword.enabled")
+      ) {
+        let value = makeActionUrl("visiturl", {
+          url: searchUrl,
+          input: searchUrl,
+        });
+        this._addMatch({
+          value,
+          comment: searchUrl,
+          style: "action visiturl",
+          frecency: Infinity,
+        });
+
+        return true;
+      }
+      return false;
+    }
+
+    // If the URI cannot be fixed or the preferred URI would do a keyword search,
+    // that basically means this isn't useful to us. Note that
+    // fixupInfo.keywordAsSent will never be true if the keyword.enabled pref
+    // is false or there are no engines, so in that case we will always return
+    // a "visit".
+    if (!fixupInfo.fixedURI || fixupInfo.keywordAsSent) {
+      return false;
+    }
+
+    let uri = fixupInfo.fixedURI;
+    // Check the host, as "http:///" is a valid nsIURI, but not useful to us.
+    // But, some schemes are expected to have no host. So we check just against
+    // schemes we know should have a host. This allows new schemes to be
+    // implemented without us accidentally blocking access to them.
+    let hostExpected = ["http", "https", "ftp", "chrome"].includes(uri.scheme);
+    if (hostExpected && !uri.host) {
+      return false;
+    }
+
+    // getFixupURIInfo() escaped the URI, so it may not be pretty.  Embed the
+    // escaped URL in the action URI since that URL should be "canonical".  But
+    // pass the pretty, unescaped URL as the match comment, since it's likely
+    // to be displayed to the user, and in any case the front-end should not
+    // rely on it being canonical.
+    let escapedURL = uri.displaySpec;
+    let displayURL = Services.textToSubURI.unEscapeURIForUI(escapedURL);
+
+    let value = makeActionUrl("visiturl", {
+      url: escapedURL,
+      input: searchUrl,
+    });
+
+    let match = {
+      value,
+      comment: displayURL,
+      style: "action visiturl",
+      frecency: Infinity,
+    };
+
+    // We don't know if this url is in Places or not, and checking that would
+    // be expensive. Thus we also don't know if we may have an icon.
+    // If we'd just try to fetch the icon for the typed string, we'd cause icon
+    // flicker, since the url keeps changing while the user types.
+    // By default we won't provide an icon, but for the subset of urls with a
+    // host we'll check for a typed slash and set favicon for the host part.
+    if (
+      hostExpected &&
+      (searchUrl.endsWith("/") || uri.pathQueryRef.length > 1)
+    ) {
+      match.icon = `page-icon:${uri.prePath}/`;
+    }
+
+    this._addMatch(match);
+    return true;
+  },
+
   _onResultRow(row, cancel) {
     let queryType = row.getResultByIndex(QUERYINDEX_QUERYTYPE);
     switch (queryType) {
diff --git a/toolkit/components/places/tests/unifiedcomplete/autofill_tasks.js b/toolkit/components/places/tests/unifiedcomplete/autofill_tasks.js
index 088ccb6c8ce02..439ce5b26b04d 100644
--- a/toolkit/components/places/tests/unifiedcomplete/autofill_tasks.js
+++ b/toolkit/components/places/tests/unifiedcomplete/autofill_tasks.js
@@ -591,14 +591,15 @@ function addAutofillTasks(origins) {
     }
 
     // Enable actions.  In the `origins` case, the failure to make an autofill
-    // match means UnifiedComplete should not create a heuristic result. In the
-    // `!origins` case, autofill should still happen since there's no threshold
-    // comparison.
+    // match should not interrupt creating another type of heuristic match, in
+    // this case a search (for "ex").  In the `!origins` case, autofill should
+    // still happen since there's no threshold comparison.
     if (origins) {
       await check_autocomplete({
         search,
         searchParam: "enable-actions",
         matches: [
+          makeSearchMatch(search, { style: ["heuristic"] }),
           {
             value: "https://not-" + url,
             comment: "test visit for https://not-" + url,
diff --git a/toolkit/components/places/tests/unifiedcomplete/head_autocomplete.js b/toolkit/components/places/tests/unifiedcomplete/head_autocomplete.js
index 56536a7102ddc..b65acfe1575a7 100644
--- a/toolkit/components/places/tests/unifiedcomplete/head_autocomplete.js
+++ b/toolkit/components/places/tests/unifiedcomplete/head_autocomplete.js
@@ -298,24 +298,20 @@ async function check_autocomplete(test) {
     if (matches.length) {
       let firstIndexToCheck = 0;
       if (test.searchParam && test.searchParam.includes("enable-actions")) {
+        firstIndexToCheck = 1;
+        info("Checking first match is first autocomplete entry");
         let result = {
           value: controller.getValueAt(0),
           comment: controller.getCommentAt(0),
           style: controller.getStyleAt(0),
           image: controller.getImageAt(0),
         };
-        // We only care about the positioning of the first result if it is
-        // heuristic.
-        if (result.style.includes("heuristic")) {
-          info("Checking first match is first autocomplete entry");
-          info(`First match is "${result.value}", "${result.comment}"`);
-          Assert.ok(
-            await _check_autocomplete_matches(matches[0], result),
-            "first item is correct"
-          );
-          info("Checking rest of the matches");
-          firstIndexToCheck = 1;
-        }
+        info(`First match is "${result.value}", "${result.comment}"`);
+        Assert.ok(
+          await _check_autocomplete_matches(matches[0], result),
+          "first item is correct"
+        );
+        info("Checking rest of the matches");
       }
 
       for (let i = firstIndexToCheck; i < controller.matchCount; i++) {
diff --git a/toolkit/components/places/tests/unifiedcomplete/test_empty_search.js b/toolkit/components/places/tests/unifiedcomplete/test_empty_search.js
index 733a12dd3bcf7..9880f649e91dc 100644
--- a/toolkit/components/places/tests/unifiedcomplete/test_empty_search.js
+++ b/toolkit/components/places/tests/unifiedcomplete/test_empty_search.js
@@ -40,6 +40,7 @@ add_task(async function test_javascript_match() {
     search: "foo",
     searchParam: "enable-actions",
     matches: [
+      makeSearchMatch("foo", { heuristic: true }),
       { uri: uri1, title: "title" },
       { uri: uri2, title: "title", style: ["bookmark"] },
       { uri: uri3, title: "title" },
diff --git a/toolkit/components/places/tests/unifiedcomplete/test_keyword_search_actions.js b/toolkit/components/places/tests/unifiedcomplete/test_keyword_search_actions.js
index 35be972a8a318..65382cc094632 100644
--- a/toolkit/components/places/tests/unifiedcomplete/test_keyword_search_actions.js
+++ b/toolkit/components/places/tests/unifiedcomplete/test_keyword_search_actions.js
@@ -251,6 +251,18 @@ add_task(async function test_keyword_search() {
     ],
   });
 
+  info("Bug 420328: no-param keyword with a param");
+  await check_autocomplete({
+    search: "noparam foo",
+    searchParam: "enable-actions",
+    matches: [makeSearchMatch("noparam foo", { heuristic: true })],
+  });
+  await check_autocomplete({
+    search: "post_noparam foo",
+    searchParam: "enable-actions",
+    matches: [makeSearchMatch("post_noparam foo", { heuristic: true })],
+  });
+
   info("escaping with default UTF-8 charset");
   await check_autocomplete({
     search: "encoded foé",
diff --git a/toolkit/components/places/tests/unifiedcomplete/test_remote_tab_matches.js b/toolkit/components/places/tests/unifiedcomplete/test_remote_tab_matches.js
index c1575065383b3..59a061199f752 100644
--- a/toolkit/components/places/tests/unifiedcomplete/test_remote_tab_matches.js
+++ b/toolkit/components/places/tests/unifiedcomplete/test_remote_tab_matches.js
@@ -66,6 +66,28 @@ function makeRemoteTabMatch(url, deviceName, extra = {}) {
   };
 }
 
+// The tests.
+add_task(async function test_nomatch() {
+  // Nothing matches.
+  configureEngine({
+    guid_desktop: {
+      id: "desktop",
+      tabs: [
+        {
+          urlHistory: ["http://foo.com/"],
+        },
+      ],
+    },
+  });
+
+  // No remote tabs match here, so we only expect search results.
+  await check_autocomplete({
+    search: "ex",
+    searchParam: "enable-actions",
+    matches: [makeSearchMatch("ex", { heuristic: true })],
+  });
+});
+
 add_task(async function test_minimal() {
   // The minimal client and tabs info we can get away with.
   configureEngine({
@@ -82,7 +104,10 @@ add_task(async function test_minimal() {
   await check_autocomplete({
     search: "ex",
     searchParam: "enable-actions",
-    matches: [makeRemoteTabMatch("http://example.com/", "My Desktop")],
+    matches: [
+      makeSearchMatch("ex", { heuristic: true }),
+      makeRemoteTabMatch("http://example.com/", "My Desktop"),
+    ],
   });
 });
 
@@ -105,6 +130,7 @@ add_task(async function test_maximal() {
     search: "ex",
     searchParam: "enable-actions",
     matches: [
+      makeSearchMatch("ex", { heuristic: true }),
       makeRemoteTabMatch("http://example.com/", "My Phone", {
         title: "An Example",
         icon: "moz-anno:favicon:http://favicon/",
@@ -132,6 +158,7 @@ add_task(async function test_noShowIcons() {
     search: "ex",
     searchParam: "enable-actions",
     matches: [
+      makeSearchMatch("ex", { heuristic: true }),
       makeRemoteTabMatch("http://example.com/", "My Phone", {
         title: "An Example",
         // expecting the default favicon due to that pref.
@@ -160,7 +187,7 @@ add_task(async function test_dontMatchSyncedTabs() {
   await check_autocomplete({
     search: "ex",
     searchParam: "enable-actions",
-    matches: [],
+    matches: [makeSearchMatch("ex", { heuristic: true })],
   });
   Services.prefs.clearUserPref("services.sync.syncedTabs.showRemoteTabs");
 });
@@ -183,6 +210,7 @@ add_task(async function test_matches_title() {
     search: "ex",
     searchParam: "enable-actions",
     matches: [
+      makeSearchMatch("ex", { heuristic: true }),
       makeRemoteTabMatch("http://foo.com/", "My Phone", {
         title: "An Example",
       }),
@@ -215,7 +243,10 @@ add_task(async function test_localtab_matches_override() {
   await check_autocomplete({
     search: "ex",
     searchParam: "enable-actions",
-    matches: [makeSwitchToTabMatch("http://foo.com/", { title: "An Example" })],
+    matches: [
+      makeSearchMatch("ex", { heuristic: true }),
+      makeSwitchToTabMatch("http://foo.com/", { title: "An Example" }),
+    ],
   });
   await removeOpenPages(uri, 1);
 });
@@ -244,6 +275,7 @@ add_task(async function test_remotetab_matches_override() {
     search: "rem",
     searchParam: "enable-actions",
     matches: [
+      makeSearchMatch("rem", { heuristic: true }),
       makeRemoteTabMatch("http://foo.remote.com/", "My Phone", {
         title: "An Example",
       }),
@@ -280,6 +312,7 @@ add_task(async function test_many_remotetab_matches() {
     searchParam: "enable-actions",
     checkSorting: true,
     matches: [
+      makeSearchMatch("rem", { heuristic: true }),
       makeRemoteTabMatch("http://foo.remote.com/0", "My Phone", {
         title: "A title",
       }),
@@ -328,12 +361,15 @@ add_task(async function test_maxResults() {
     },
   });
 
-  // Set maxResults to 4 in our search.
+  // Set maxResults to 5 in our search.  5 results total should be returned: the
+  // heuristic followed by ceil(maxResults / 2) remote tabs, then two more
+  // remote tabs to round out the number of results to 5.
   await check_autocomplete({
     search: "rem",
-    searchParam: "enable-actions max-results:4",
+    searchParam: "enable-actions max-results:5",
     checkSorting: true,
     matches: [
+      makeSearchMatch("rem", { heuristic: true }),
       makeRemoteTabMatch("http://foo.remote.com/0", "My Phone", {
         title: "A title",
       }),
@@ -373,14 +409,15 @@ add_task(async function test_restrictionCharacter() {
   await PlacesTestUtils.addVisits([{ uri, title: "An Example" }]);
   await addOpenPages(uri, 1);
 
-  // Set maxResults to 7 in our search.  7 results should be returned:
-  // ceil(maxResults / 2) remote tabs, then the open tab, then 2 more remote tab
-  // results to get to 7 total.
+  // Set maxResults to 8 in our search.  8 results should be returned: the
+  // heuristic followed by (maxResults / 2) remote tabs, then the open tab, then
+  // 2 more remote tab results to get to 8 total.
   await check_autocomplete({
     search: UrlbarTokenizer.RESTRICT.OPENPAGE,
-    searchParam: "enable-actions max-results:7",
+    searchParam: "enable-actions max-results:8",
     checkSorting: true,
     matches: [
+      makeSearchMatch(UrlbarTokenizer.RESTRICT.OPENPAGE, { heuristic: true }),
       makeRemoteTabMatch("http://foo.remote.com/0", "My Phone", {
         title: "A title",
       }),
diff --git a/toolkit/components/places/tests/unifiedcomplete/test_restrict_searchstring.js b/toolkit/components/places/tests/unifiedcomplete/test_restrict_searchstring.js
new file mode 100644
index 0000000000000..ea97021b62259
--- /dev/null
+++ b/toolkit/components/places/tests/unifiedcomplete/test_restrict_searchstring.js
@@ -0,0 +1,32 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Test that restriction tokens are not removed from the search string, apart
+ * from a leading search restriction token.
+ */
+
+add_task(async function test_searchstring() {
+  for (let token of Object.values(UrlbarTokenizer.RESTRICT)) {
+    for (let search of [`${token} query`, `query ${token}`]) {
+      let searchQuery =
+        token == UrlbarTokenizer.RESTRICT.SEARCH &&
+        search.startsWith(UrlbarTokenizer.RESTRICT.SEARCH)
+          ? search.substring(2)
+          : search;
+      info(`Searching for "${search}", expecting "${searchQuery}"`);
+      await check_autocomplete({
+        search,
+        searchParam: "enable-actions",
+        matches: [
+          makeSearchMatch(search, {
+            engineName: "MozSearch",
+            searchQuery,
+            heuristic: true,
+          }),
+        ],
+      });
+    }
+  }
+});
diff --git a/toolkit/components/places/tests/unifiedcomplete/test_search_engine_alias.js b/toolkit/components/places/tests/unifiedcomplete/test_search_engine_alias.js
index 4dc5ec6da56b1..9887c4676eea4 100644
--- a/toolkit/components/places/tests/unifiedcomplete/test_search_engine_alias.js
+++ b/toolkit/components/places/tests/unifiedcomplete/test_search_engine_alias.js
@@ -111,6 +111,30 @@ add_task(async function basicGetAndPost() {
         }),
       ],
     });
+
+    // When a restriction token is used before the alias, the alias should *not*
+    // be recognized.  It should be treated as part of the search string.  Try
+    // all the restriction tokens to test that.  We should get a single "search
+    // with" heuristic result without an alias.
+    for (let token of Object.values(UrlbarTokenizer.RESTRICT)) {
+      let search = `${token} ${alias} query string`;
+      let searchQuery =
+        token == UrlbarTokenizer.RESTRICT.SEARCH &&
+        search.startsWith(UrlbarTokenizer.RESTRICT.SEARCH)
+          ? search.substring(2)
+          : search;
+      await check_autocomplete({
+        search,
+        searchParam: "enable-actions",
+        matches: [
+          makeSearchMatch(search, {
+            engineName: "MozSearch",
+            searchQuery,
+            heuristic: true,
+          }),
+        ],
+      });
+    }
   }
   await cleanup();
 });
diff --git a/toolkit/components/places/tests/unifiedcomplete/test_search_engine_default.js b/toolkit/components/places/tests/unifiedcomplete/test_search_engine_default.js
new file mode 100644
index 0000000000000..81d1b6e7accb3
--- /dev/null
+++ b/toolkit/components/places/tests/unifiedcomplete/test_search_engine_default.js
@@ -0,0 +1,55 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+add_task(async function() {
+  // Note that head_autocomplete.js has already added a MozSearch engine.
+  // Here we add another engine with a search alias.
+  await Services.search.addEngineWithDetails("AliasedMozSearch", {
+    alias: "doit",
+    method: "GET",
+    template: "http://s.example.com/search",
+  });
+
+  info("search engine");
+  await check_autocomplete({
+    search: "mozilla",
+    searchParam: "enable-actions",
+    matches: [makeSearchMatch("mozilla", { heuristic: true })],
+  });
+
+  info("search engine, uri-like input");
+  await check_autocomplete({
+    search: "http:///",
+    searchParam: "enable-actions",
+    matches: [makeSearchMatch("http:///", { heuristic: true })],
+  });
+
+  info("search engine, multiple words");
+  await check_autocomplete({
+    search: "mozzarella cheese",
+    searchParam: "enable-actions",
+    matches: [makeSearchMatch("mozzarella cheese", { heuristic: true })],
+  });
+
+  info("search engine, after current engine has changed");
+  await Services.search.addEngineWithDetails("MozSearch2", {
+    method: "GET",
+    template: "http://s.example.com/search2",
+  });
+  let engine = Services.search.getEngineByName("MozSearch2");
+  notEqual(
+    Services.search.defaultEngine,
+    engine,
+    "New engine shouldn't be the current engine yet"
+  );
+  await Services.search.setDefault(engine);
+  await check_autocomplete({
+    search: "mozilla",
+    searchParam: "enable-actions",
+    matches: [
+      makeSearchMatch("mozilla", { engineName: "MozSearch2", heuristic: true }),
+    ],
+  });
+
+  await cleanup();
+});
diff --git a/toolkit/components/places/tests/unifiedcomplete/test_tab_matches.js b/toolkit/components/places/tests/unifiedcomplete/test_tab_matches.js
index 5cb4d790b1e13..42c3b566a8665 100644
--- a/toolkit/components/places/tests/unifiedcomplete/test_tab_matches.js
+++ b/toolkit/components/places/tests/unifiedcomplete/test_tab_matches.js
@@ -25,11 +25,15 @@ add_task(async function test_tab_matches() {
   await addOpenPages(uri3, 1);
   await addOpenPages(uri4, 1);
 
-  info("basic tab match");
+  info("two results, normal result is a tab match");
   await check_autocomplete({
     search: "abc.com",
     searchParam: "enable-actions",
-    matches: [makeSwitchToTabMatch("http://abc.com/", { title: "ABC rocks" })],
+    matches: [
+      makeVisitMatch("abc.com", "http://abc.com/", { heuristic: true }),
+      makeSwitchToTabMatch("http://abc.com/", { title: "ABC rocks" }),
+      makeSearchMatch("abc.com", { heuristic: false }),
+    ],
   });
 
   info("three results, one tab match");
@@ -37,6 +41,7 @@ add_task(async function test_tab_matches() {
     search: "abc",
     searchParam: "enable-actions",
     matches: [
+      makeSearchMatch("abc", { heuristic: true }),
       makeSwitchToTabMatch("http://abc.com/", { title: "ABC rocks" }),
       {
         uri: uri2,
@@ -57,6 +62,7 @@ add_task(async function test_tab_matches() {
     search: "abc",
     searchParam: "enable-actions",
     matches: [
+      makeSearchMatch("abc", { heuristic: true }),
       makeSwitchToTabMatch("http://abc.com/", { title: "ABC rocks" }),
       makeSwitchToTabMatch("http://xyz.net/", {
         title: "xyz.net - we're better than ABC",
@@ -75,6 +81,7 @@ add_task(async function test_tab_matches() {
     search: "abc",
     searchParam: "enable-actions",
     matches: [
+      makeSearchMatch("abc", { heuristic: true }),
       makeSwitchToTabMatch("http://abc.com/", { title: "ABC rocks" }),
       makeSwitchToTabMatch("http://xyz.net/", {
         title: "xyz.net - we're better than ABC",
@@ -94,6 +101,7 @@ add_task(async function test_tab_matches() {
     search: "abc",
     searchParam: "enable-actions user-context-id:3",
     matches: [
+      makeSearchMatch("abc", { heuristic: true }),
       makeSwitchToTabMatch("http://foobar.org/", {
         title: "foobar.org - much better than ABC, definitely better than XYZ",
       }),
@@ -111,6 +119,7 @@ add_task(async function test_tab_matches() {
     search: "abc",
     searchParam: "enable-actions user-context-id:2",
     matches: [
+      makeSearchMatch("abc", { heuristic: true }),
       { uri: uri1, title: "ABC rocks", style: ["favicon"] },
       {
         uri: uri2,
@@ -133,6 +142,7 @@ add_task(async function test_tab_matches() {
     search: "abc",
     searchParam: "enable-actions",
     matches: [
+      makeSearchMatch("abc", { heuristic: true }),
       makeSwitchToTabMatch("http://abc.com/", { title: "ABC rocks" }),
       makeSwitchToTabMatch("http://xyz.net/", {
         title: "xyz.net - we're better than ABC",
@@ -150,6 +160,7 @@ add_task(async function test_tab_matches() {
     search: "abc",
     searchParam: "enable-actions disable-private-actions",
     matches: [
+      makeSearchMatch("abc", { heuristic: true }),
       { uri: uri1, title: "ABC rocks", style: ["favicon"] },
       {
         uri: uri2,
@@ -184,12 +195,13 @@ add_task(async function test_tab_matches() {
   });
 
   info("three results, no tab matches");
-  await removeOpenPages(uri1, 1);
-  await removeOpenPages(uri2, 6);
+  removeOpenPages(uri1, 1);
+  removeOpenPages(uri2, 6);
   await check_autocomplete({
     search: "abc",
     searchParam: "enable-actions",
     matches: [
+      makeSearchMatch("abc", { heuristic: true }),
       { uri: uri1, title: "ABC rocks", style: ["favicon"] },
       {
         uri: uri2,
@@ -209,28 +221,46 @@ add_task(async function test_tab_matches() {
   await check_autocomplete({
     search: UrlbarTokenizer.RESTRICT.OPENPAGE + " abc",
     searchParam: "enable-actions",
-    matches: [makeSwitchToTabMatch("http://abc.com/", { title: "ABC rocks" })],
+    matches: [
+      makeSearchMatch(UrlbarTokenizer.RESTRICT.OPENPAGE + " abc", {
+        heuristic: true,
+        searchQuery: UrlbarTokenizer.RESTRICT.OPENPAGE + " abc",
+      }),
+      makeSwitchToTabMatch("http://abc.com/", { title: "ABC rocks" }),
+    ],
   });
 
   info("tab match with not-addable pages");
   await check_autocomplete({
     search: "mozilla",
     searchParam: "enable-actions",
-    matches: [makeSwitchToTabMatch("about:mozilla")],
+    matches: [
+      makeSearchMatch("mozilla", { heuristic: true }),
+      makeSwitchToTabMatch("about:mozilla"),
+    ],
   });
 
   info("tab match with not-addable pages, no boundary search");
   await check_autocomplete({
     search: "ut:mo",
     searchParam: "enable-actions",
-    matches: [makeSwitchToTabMatch("about:mozilla")],
+    matches: [
+      makeSearchMatch("ut:mo", { heuristic: true }),
+      makeSwitchToTabMatch("about:mozilla"),
+    ],
   });
 
   info("tab match with not-addable pages and restriction character");
   await check_autocomplete({
     search: UrlbarTokenizer.RESTRICT.OPENPAGE + " mozilla",
     searchParam: "enable-actions",
-    matches: [makeSwitchToTabMatch("about:mozilla")],
+    matches: [
+      makeSearchMatch(UrlbarTokenizer.RESTRICT.OPENPAGE + " mozilla", {
+        heuristic: true,
+        searchQuery: UrlbarTokenizer.RESTRICT.OPENPAGE + " mozilla",
+      }),
+      makeSwitchToTabMatch("about:mozilla"),
+    ],
   });
 
   info("tab match with not-addable pages and only restriction character");
@@ -238,6 +268,7 @@ add_task(async function test_tab_matches() {
     search: UrlbarTokenizer.RESTRICT.OPENPAGE,
     searchParam: "enable-actions",
     matches: [
+      makeSearchMatch(UrlbarTokenizer.RESTRICT.OPENPAGE, { heuristic: true }),
       makeSwitchToTabMatch("http://abc.com/", { title: "ABC rocks" }),
       makeSwitchToTabMatch("about:mozilla"),
       makeSwitchToTabMatch("data:text/html,test"),
@@ -255,7 +286,11 @@ add_task(async function test_tab_matches() {
   await check_autocomplete({
     search: "abc.com",
     searchParam: "enable-actions",
-    matches: [makeSwitchToTabMatch("http://abc.com/", { title: "ABC rocks" })],
+    matches: [
+      makeVisitMatch("abc.com", "http://abc.com/", { heuristic: true }),
+      makeSwitchToTabMatch("http://abc.com/", { title: "ABC rocks" }),
+      makeSearchMatch("abc.com", { heuristic: false }),
+    ],
   });
   await PlacesUtils.bookmarks.remove(bm);
 
diff --git a/toolkit/components/places/tests/unifiedcomplete/test_visit_url.js b/toolkit/components/places/tests/unifiedcomplete/test_visit_url.js
new file mode 100644
index 0000000000000..05ba806f8610f
--- /dev/null
+++ b/toolkit/components/places/tests/unifiedcomplete/test_visit_url.js
@@ -0,0 +1,350 @@
+add_task(async function() {
+  info("visit url, no protocol");
+  await check_autocomplete({
+    search: "mozilla.org",
+    searchParam: "enable-actions",
+    matches: [
+      {
+        uri: makeActionURI("visiturl", {
+          url: "http://mozilla.org/",
+          input: "mozilla.org",
+        }),
+        title: "http://mozilla.org/",
+        style: ["action", "visiturl", "heuristic"],
+      },
+      {
+        uri: makeActionURI("searchengine", {
+          engineName: "MozSearch",
+          input: "mozilla.org",
+          searchQuery: "mozilla.org",
+        }),
+        title: "MozSearch",
+        style: ["action", "searchengine"],
+      },
+    ],
+  });
+
+  info("visit url, no protocol but with 2 dots");
+  await check_autocomplete({
+    search: "www.mozilla.org",
+    searchParam: "enable-actions",
+    matches: [
+      {
+        uri: makeActionURI("visiturl", {
+          url: "http://www.mozilla.org/",
+          input: "www.mozilla.org",
+        }),
+        title: "http://www.mozilla.org/",
+        style: ["action", "visiturl", "heuristic"],
+      },
+      {
+        uri: makeActionURI("searchengine", {
+          engineName: "MozSearch",
+          input: "www.mozilla.org",
+          searchQuery: "www.mozilla.org",
+        }),
+        title: "MozSearch",
+        style: ["action", "searchengine"],
+      },
+    ],
+  });
+
+  info("visit url, no protocol, e-mail like");
+  await check_autocomplete({
+    search: "a@b.com",
+    searchParam: "enable-actions",
+    matches: [
+      {
+        uri: makeActionURI("visiturl", {
+          url: "http://a@b.com/",
+          input: "a@b.com",
+        }),
+        title: "http://a@b.com/",
+        style: ["action", "visiturl", "heuristic"],
+      },
+      {
+        uri: makeActionURI("searchengine", {
+          engineName: "MozSearch",
+          input: "a@b.com",
+          searchQuery: "a@b.com",
+        }),
+        title: "MozSearch",
+        style: ["action", "searchengine"],
+      },
+    ],
+  });
+
+  info("visit url, with protocol but with 2 dots");
+  await check_autocomplete({
+    search: "https://www.mozilla.org",
+    searchParam: "enable-actions",
+    matches: [
+      {
+        uri: makeActionURI("visiturl", {
+          url: "https://www.mozilla.org/",
+          input: "https://www.mozilla.org",
+        }),
+        title: "https://www.mozilla.org/",
+        style: ["action", "visiturl", "heuristic"],
+      },
+    ],
+  });
+
+  info("visit url, with protocol but with 3 dots");
+  await check_autocomplete({
+    search: "https://www.mozilla.org.tw",
+    searchParam: "enable-actions",
+    matches: [
+      {
+        uri: makeActionURI("visiturl", {
+          url: "https://www.mozilla.org.tw/",
+          input: "https://www.mozilla.org.tw",
+        }),
+        title: "https://www.mozilla.org.tw/",
+        style: ["action", "visiturl", "heuristic"],
+      },
+    ],
+  });
+
+  info("visit url, with protocol");
+  await check_autocomplete({
+    search: "https://mozilla.org",
+    searchParam: "enable-actions",
+    matches: [
+      {
+        uri: makeActionURI("visiturl", {
+          url: "https://mozilla.org/",
+          input: "https://mozilla.org",
+        }),
+        title: "https://mozilla.org/",
+        style: ["action", "visiturl", "heuristic"],
+      },
+    ],
+  });
+
+  info("visit url, about: protocol (no host)");
+  await check_autocomplete({
+    search: "about:nonexistent",
+    searchParam: "enable-actions",
+    matches: [
+      {
+        uri: makeActionURI("visiturl", {
+          url: "about:nonexistent",
+          input: "about:nonexistent",
+        }),
+        title: "about:nonexistent",
+        style: ["action", "visiturl", "heuristic"],
+      },
+    ],
+  });
+
+  info("visit url, with non-standard whitespace");
+  await check_autocomplete({
+    search: "https://www.mozilla.org\u2028",
+    searchParam: "enable-actions",
+    matches: [
+      {
+        uri: makeActionURI("visiturl", {
+          url: "https://www.mozilla.org/",
+          input: "https://www.mozilla.org",
+        }),
+        title: "https://www.mozilla.org/",
+        style: ["action", "visiturl", "heuristic"],
+      },
+    ],
+  });
+
+  // This is distinct because of how we predict being able to url autofill via
+  // host lookups.
+  info("visit url, host matching visited host but not visited url");
+  await PlacesTestUtils.addVisits([
+    {
+      uri: NetUtil.newURI("http://mozilla.org/wine/"),
+      title: "Mozilla Wine",
+      transition: TRANSITION_TYPED,
+    },
+  ]);
+  await check_autocomplete({
+    search: "mozilla.org/rum",
+    searchParam: "enable-actions",
+    matches: [
+      makeVisitMatch("mozilla.org/rum", "http://mozilla.org/rum", {
+        heuristic: true,
+      }),
+    ],
+  });
+
+  // And hosts with no dot in them are special, due to requiring whitelisting.
+  info("non-whitelisted host");
+  await check_autocomplete({
+    search: "firefox",
+    searchParam: "enable-actions",
+    matches: [makeSearchMatch("firefox", { heuristic: true })],
+  });
+
+  info("string with non-whitelisted host");
+  if (Services.prefs.getBoolPref("browser.fixup.defaultToSearch", true)) {
+    await check_autocomplete({
+      search: "firefox/get",
+      searchParam: "enable-actions",
+      matches: [makeSearchMatch("firefox/get", { heuristic: true })],
+    });
+  } else {
+    await check_autocomplete({
+      search: "firefox/get",
+      searchParam: "enable-actions",
+      matches: [
+        makeVisitMatch("firefox/get", "http://firefox/get", {
+          heuristic: true,
+        }),
+      ],
+    });
+  }
+
+  Services.prefs.setBoolPref("browser.fixup.domainwhitelist.firefox", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("browser.fixup.domainwhitelist.firefox");
+  });
+
+  info("whitelisted host");
+  await check_autocomplete({
+    search: "firefox",
+    searchParam: "enable-actions",
+    matches: [
+      makeVisitMatch("firefox", "http://firefox/", { heuristic: true }),
+      makeSearchMatch("firefox", { heuristic: false }),
+    ],
+  });
+
+  info("url with whitelisted host");
+  await check_autocomplete({
+    search: "firefox/get",
+    searchParam: "enable-actions",
+    matches: [
+      makeVisitMatch("firefox/get", "http://firefox/get", { heuristic: true }),
+    ],
+  });
+
+  info(
+    "visit url, host matching visited host but not visited url, whitelisted host"
+  );
+  Services.prefs.setBoolPref("browser.fixup.domainwhitelist.mozilla", true);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("browser.fixup.domainwhitelist.mozilla");
+  });
+  await check_autocomplete({
+    search: "mozilla/rum",
+    searchParam: "enable-actions",
+    matches: [
+      makeVisitMatch("mozilla/rum", "http://mozilla/rum", { heuristic: true }),
+    ],
+  });
+
+  // ipv4 and ipv6 literal addresses should offer to visit.
+  info("visit url, ipv4 literal");
+  await check_autocomplete({
+    search: "127.0.0.1",
+    searchParam: "enable-actions",
+    matches: [
+      makeVisitMatch("127.0.0.1", "http://127.0.0.1/", { heuristic: true }),
+    ],
+  });
+
+  info("visit url, ipv6 literal");
+  await check_autocomplete({
+    search: "[2001:db8::1]",
+    searchParam: "enable-actions",
+    matches: [
+      makeVisitMatch("[2001:db8::1]", "http://[2001:db8::1]/", {
+        heuristic: true,
+      }),
+    ],
+  });
+
+  // Setting keyword.enabled to false should always try to visit.
+  let keywordEnabled = Services.prefs.getBoolPref("keyword.enabled");
+  Services.prefs.setBoolPref("keyword.enabled", false);
+  registerCleanupFunction(() => {
+    Services.prefs.clearUserPref("keyword.enabled");
+  });
+  info("visit url, keyword.enabled = false");
+  await check_autocomplete({
+    search: "bacon",
+    searchParam: "enable-actions",
+    matches: [makeVisitMatch("bacon", "http://bacon/", { heuristic: true })],
+  });
+  info("visit two word query, keyword.enabled = false");
+  await check_autocomplete({
+    search: "bacon lovers",
+    searchParam: "enable-actions",
+    matches: [
+      makeVisitMatch("bacon lovers", "bacon lovers", { heuristic: true }),
+    ],
+  });
+  Services.prefs.setBoolPref("keyword.enabled", keywordEnabled);
+
+  info("visit url, scheme+host");
+  await check_autocomplete({
+    search: "http://example",
+    searchParam: "enable-actions",
+    matches: [
+      makeVisitMatch("http://example", "http://example/", { heuristic: true }),
+    ],
+  });
+
+  info("visit url, scheme+host");
+  await check_autocomplete({
+    search: "ftp://example",
+    searchParam: "enable-actions",
+    matches: [
+      makeVisitMatch("ftp://example", "ftp://example/", { heuristic: true }),
+    ],
+  });
+
+  info("visit url, host+port");
+  await check_autocomplete({
+    search: "example:8080",
+    searchParam: "enable-actions",
+    matches: [
+      makeVisitMatch("example:8080", "http://example:8080/", {
+        heuristic: true,
+      }),
+    ],
+  });
+
+  info("numerical operations that look like urls should search");
+  await check_autocomplete({
+    search: "123/12",
+    searchParam: "enable-actions",
+    matches: [makeSearchMatch("123/12", { heuristic: true })],
+  });
+
+  info("numerical operations that look like urls should search");
+  await check_autocomplete({
+    search: "123.12/12.1",
+    searchParam: "enable-actions",
+    matches: [makeSearchMatch("123.12/12.1", { heuristic: true })],
+  });
+
+  info("access resource:///modules");
+  await check_autocomplete({
+    search: "resource:///modules",
+    searchParam: "enable-actions",
+    matches: [
+      makeVisitMatch("resource:///modules", "resource:///modules", {
+        heuristic: true,
+      }),
+    ],
+  });
+
+  info("access resource://app/modules");
+  await check_autocomplete({
+    search: "resource://app/modules",
+    searchParam: "enable-actions",
+    matches: [
+      makeVisitMatch("resource://app/modules", "resource://app/modules", {
+        heuristic: true,
+      }),
+    ],
+  });
+});
diff --git a/toolkit/components/places/tests/unifiedcomplete/xpcshell.ini b/toolkit/components/places/tests/unifiedcomplete/xpcshell.ini
index 992dccb38a7c9..72de101233e1e 100644
--- a/toolkit/components/places/tests/unifiedcomplete/xpcshell.ini
+++ b/toolkit/components/places/tests/unifiedcomplete/xpcshell.ini
@@ -40,11 +40,14 @@ support-files =
 [test_query_url.js]
 [test_remote_tab_matches.js]
 skip-if = !sync
+[test_restrict_searchstring.js]
 [test_search_engine_alias.js]
+[test_search_engine_default.js]
 [test_search_engine_host.js]
 [test_search_engine_restyle.js]
 [test_special_search.js]
 [test_swap_protocol.js]
 [test_tab_matches.js]
 [test_trimming.js]
+[test_visit_url.js]
 [test_word_boundary_search.js]
diff --git a/tools/lint/rejected-words.yml b/tools/lint/rejected-words.yml
index e45ff25f9e534..fcdba559c3748 100644
--- a/tools/lint/rejected-words.yml
+++ b/tools/lint/rejected-words.yml
@@ -69,7 +69,6 @@ avoid-blacklist-and-whitelist:
         - browser/components/uitour/UITourChild.jsm
         - browser/components/urlbar/tests/browser/browser_searchSingleWordNotification.js
         - browser/components/urlbar/tests/browser/browser_UrlbarInput_trimURLs.js
-        - browser/components/urlbar/tests/unit/test_providerHeuristicFallback.js
         - browser/components/urlbar/tests/unit/test_search_suggestions.js
         - browser/components/urlbar/tests/unit/test_tokenizer.js
         - browser/extensions/formautofill/FormAutofillSync.jsm
@@ -358,6 +357,7 @@ avoid-blacklist-and-whitelist:
         - toolkit/components/crashes/tests/xpcshell/test_crash_manager.js
         - toolkit/components/extensions/Extension.jsm
         - toolkit/components/extensions/test/xpcshell/test_WebExtensionPolicy.js
+        - toolkit/components/places/tests/unifiedcomplete/test_visit_url.js
         - toolkit/components/remotepagemanager/RemotePageManagerParent.jsm
         - toolkit/components/reputationservice/ApplicationReputation.cpp
         - toolkit/components/reputationservice/chromium/chrome/common/safe_browsing/csd.pb.h