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lib/web/fetch/request.js

@@ -477,7 +477,7 @@ class Request {
       // 4. If headers is a Headers object, then for each header in its header
       // list, append header’s name/header’s value to this’s headers.
       if (headers instanceof HeadersList) {
-        const rawList = headersList.entriesRawList
+        const rawList = headers.entriesRawList
         // TODO: optimizing this.
         for (let i = 0; i < rawList.length; ++i) {
           const { 0: key, 1: value } = rawList[i]