diff --git a/browser/extensions/webcompat/manifest.json b/browser/extensions/webcompat/manifest.json
index 5cb49d6f1bba..3beaddf530ea 100644
--- a/browser/extensions/webcompat/manifest.json
+++ b/browser/extensions/webcompat/manifest.json
@@ -2,7 +2,7 @@
   "manifest_version": 2,
   "name": "Web Compatibility Interventions",
   "description": "Urgent post-release fixes for web compatibility.",
-  "version": "103.4.0",
+  "version": "103.5.0",
   "applications": {
     "gecko": {
       "id": "webcompat@mozilla.org",
diff --git a/browser/extensions/webcompat/shims/branch.js b/browser/extensions/webcompat/shims/branch.js
index 404ab78a8f35..4689f5b2c333 100644
--- a/browser/extensions/webcompat/shims/branch.js
+++ b/browser/extensions/webcompat/shims/branch.js
@@ -49,8 +49,11 @@ if (!window?.branch?.b) {
     first() {}
     getBrowserFingerprintId() {}
     getCode() {}
-    init(key, cb) {
-      cb?.(undefined, {});
+    init(key, ...args) {
+      const cb = args.pop();
+      if (typeof cb === "function") {
+        cb(undefined, {});
+      }
     }
     lastAttributedTouchData() {}
     link() {}