diff --git a/browser_patches/firefox-beta/BUILD_NUMBER b/browser_patches/firefox-beta/BUILD_NUMBER
index dcf1694c6c..9eec5ba879 100644
--- a/browser_patches/firefox-beta/BUILD_NUMBER
+++ b/browser_patches/firefox-beta/BUILD_NUMBER
@@ -1,2 +1,2 @@
-1313
-Changed: lushnikov@chromium.org Wed 29 Dec 2021 09:04:48 PM PST
+1314
+Changed: lushnikov@chromium.org Sat Jan  8 18:49:01 MSK 2022
diff --git a/browser_patches/firefox-beta/juggler/NetworkObserver.js b/browser_patches/firefox-beta/juggler/NetworkObserver.js
index 2cbe92dc38..57c477b105 100644
--- a/browser_patches/firefox-beta/juggler/NetworkObserver.js
+++ b/browser_patches/firefox-beta/juggler/NetworkObserver.js
@@ -62,6 +62,13 @@ class PageNetwork {
     this._extraHTTPHeaders = headers;
   }
 
+  combinedExtraHTTPHeaders() {
+    return [
+      ...(this._target.browserContext().extraHTTPHeaders || []),
+      ...(this._extraHTTPHeaders || []),
+    ];
+  }
+
   enableRequestInterception() {
     this._requestInterceptionEnabled = true;
   }
@@ -151,11 +158,8 @@ class NetworkRequest {
     this._expectingResumedRequest = undefined;  // { method, headers, postData }
     this._sentOnResponse = false;
 
-    const pageNetwork = this._pageNetwork;
-    if (pageNetwork) {
-      appendExtraHTTPHeaders(httpChannel, pageNetwork._target.browserContext().extraHTTPHeaders);
-      appendExtraHTTPHeaders(httpChannel, pageNetwork._extraHTTPHeaders);
-    }
+    if (this._pageNetwork)
+      appendExtraHTTPHeaders(httpChannel, this._pageNetwork.combinedExtraHTTPHeaders());
 
     this._responseBodyChunks = [];
 
@@ -241,6 +245,8 @@ class NetworkRequest {
         this.httpChannel.setRequestHeader(header.name, '', false /* merge */);
       for (const header of headers)
         this.httpChannel.setRequestHeader(header.name, header.value, false /* merge */);
+    } else if (this._pageNetwork) {
+      appendExtraHTTPHeaders(this.httpChannel, this._pageNetwork.combinedExtraHTTPHeaders());
     }
     if (method)
       this.httpChannel.requestMethod = method;
diff --git a/browser_patches/firefox/BUILD_NUMBER b/browser_patches/firefox/BUILD_NUMBER
index 0bbe571ee7..b8f8c7fdcc 100644
--- a/browser_patches/firefox/BUILD_NUMBER
+++ b/browser_patches/firefox/BUILD_NUMBER
@@ -1,2 +1,2 @@
-1312
-Changed: lushnikov@chromium.org Tue Dec 28 13:12:02 MST 2021
+1313
+Changed: lushnikov@chromium.org Sat Jan  8 18:49:01 MSK 2022
diff --git a/browser_patches/firefox/juggler/NetworkObserver.js b/browser_patches/firefox/juggler/NetworkObserver.js
index 2cbe92dc38..57c477b105 100644
--- a/browser_patches/firefox/juggler/NetworkObserver.js
+++ b/browser_patches/firefox/juggler/NetworkObserver.js
@@ -62,6 +62,13 @@ class PageNetwork {
     this._extraHTTPHeaders = headers;
   }
 
+  combinedExtraHTTPHeaders() {
+    return [
+      ...(this._target.browserContext().extraHTTPHeaders || []),
+      ...(this._extraHTTPHeaders || []),
+    ];
+  }
+
   enableRequestInterception() {
     this._requestInterceptionEnabled = true;
   }
@@ -151,11 +158,8 @@ class NetworkRequest {
     this._expectingResumedRequest = undefined;  // { method, headers, postData }
     this._sentOnResponse = false;
 
-    const pageNetwork = this._pageNetwork;
-    if (pageNetwork) {
-      appendExtraHTTPHeaders(httpChannel, pageNetwork._target.browserContext().extraHTTPHeaders);
-      appendExtraHTTPHeaders(httpChannel, pageNetwork._extraHTTPHeaders);
-    }
+    if (this._pageNetwork)
+      appendExtraHTTPHeaders(httpChannel, this._pageNetwork.combinedExtraHTTPHeaders());
 
     this._responseBodyChunks = [];
 
@@ -241,6 +245,8 @@ class NetworkRequest {
         this.httpChannel.setRequestHeader(header.name, '', false /* merge */);
       for (const header of headers)
         this.httpChannel.setRequestHeader(header.name, header.value, false /* merge */);
+    } else if (this._pageNetwork) {
+      appendExtraHTTPHeaders(this.httpChannel, this._pageNetwork.combinedExtraHTTPHeaders());
     }
     if (method)
       this.httpChannel.requestMethod = method;