diff --git a/.eslintrc.js b/.eslintrc.js
index 3643214b6ce0..895c9cefc74b 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -52,7 +52,6 @@ module.exports = {
     // XXX Bug 1452706. These directories are still being fixed, so turn off
     //  mozilla/require-expected-throws-or-rejects for now.
     "files": [
-      "devtools/client/inspector/extensions/test/head_devtools_inspector_sidebar.js",
       "storage/test/unit/**",
     ],
     "rules": {
diff --git a/devtools/client/inspector/extensions/test/head_devtools_inspector_sidebar.js b/devtools/client/inspector/extensions/test/head_devtools_inspector_sidebar.js
index e21f8ed3ef16..a15fe61e9073 100644
--- a/devtools/client/inspector/extensions/test/head_devtools_inspector_sidebar.js
+++ b/devtools/client/inspector/extensions/test/head_devtools_inspector_sidebar.js
@@ -40,7 +40,7 @@ async function expectNoSuchActorIDs(client, actors) {
   info(`Test that all the objectValueGrip actors have been released`);
   for (const actor of actors) {
     await Assert.rejects(client.request({to: actor, type: "requestTypes"}),
-                         `No such actor for ID: ${actor}`);
+                         err => err.message == `No such actor for ID: ${actor}`);
   }
 }