diff --git a/browser_patches/firefox-beta/BUILD_NUMBER b/browser_patches/firefox-beta/BUILD_NUMBER
index 31a3ff850e..70d730b8ab 100644
--- a/browser_patches/firefox-beta/BUILD_NUMBER
+++ b/browser_patches/firefox-beta/BUILD_NUMBER
@@ -1,2 +1,2 @@
-1291
-Changed: lushnikov@chromium.org Wed 08 Sep 2021 07:49:38 AM PDT
+1292
+Changed: max@schmitt.mx Fri 10 Sep 2021 17:25:22 CEST
diff --git a/browser_patches/firefox-beta/juggler/NetworkObserver.js b/browser_patches/firefox-beta/juggler/NetworkObserver.js
index 3aeb8d6b4e..d9e383adf1 100644
--- a/browser_patches/firefox-beta/juggler/NetworkObserver.js
+++ b/browser_patches/firefox-beta/juggler/NetworkObserver.js
@@ -729,6 +729,7 @@ class NetworkRequest {
         requestId: this.requestId,
         responseEndTime: httpChannel.responseEndTime,
         transferSize: httpChannel.transferSize,
+        encodedBodySize: httpChannel.encodedBodySize,
         protocolVersion: httpChannel.protocolVersion,
       }, this._frameId);
     }
diff --git a/browser_patches/firefox-beta/juggler/protocol/Protocol.js b/browser_patches/firefox-beta/juggler/protocol/Protocol.js
index 33dcb41b64..7302ca01fb 100644
--- a/browser_patches/firefox-beta/juggler/protocol/Protocol.js
+++ b/browser_patches/firefox-beta/juggler/protocol/Protocol.js
@@ -508,6 +508,7 @@ const Network = {
       requestId: t.String,
       responseEndTime: t.Number,
       transferSize: t.Number,
+      encodedBodySize: t.Number,
       protocolVersion: t.String,
     },
     'requestFailed': {
diff --git a/browser_patches/firefox/BUILD_NUMBER b/browser_patches/firefox/BUILD_NUMBER
index 8ce50dfb62..7ac974fd13 100644
--- a/browser_patches/firefox/BUILD_NUMBER
+++ b/browser_patches/firefox/BUILD_NUMBER
@@ -1,2 +1,2 @@
-1294
-Changed: lushnikov@chromium.org Wed 08 Sep 2021 06:44:52 AM PDT
+1295
+Changed: max@schmitt.mx Fri 10 Sep 2021 17:25:22 CEST
diff --git a/browser_patches/firefox/juggler/NetworkObserver.js b/browser_patches/firefox/juggler/NetworkObserver.js
index 3aeb8d6b4e..d9e383adf1 100644
--- a/browser_patches/firefox/juggler/NetworkObserver.js
+++ b/browser_patches/firefox/juggler/NetworkObserver.js
@@ -729,6 +729,7 @@ class NetworkRequest {
         requestId: this.requestId,
         responseEndTime: httpChannel.responseEndTime,
         transferSize: httpChannel.transferSize,
+        encodedBodySize: httpChannel.encodedBodySize,
         protocolVersion: httpChannel.protocolVersion,
       }, this._frameId);
     }
diff --git a/browser_patches/firefox/juggler/protocol/Protocol.js b/browser_patches/firefox/juggler/protocol/Protocol.js
index 33dcb41b64..7302ca01fb 100644
--- a/browser_patches/firefox/juggler/protocol/Protocol.js
+++ b/browser_patches/firefox/juggler/protocol/Protocol.js
@@ -508,6 +508,7 @@ const Network = {
       requestId: t.String,
       responseEndTime: t.Number,
       transferSize: t.Number,
+      encodedBodySize: t.Number,
       protocolVersion: t.String,
     },
     'requestFailed': {