diff --git a/browser/extensions/webcompat/data/ua_overrides.js b/browser/extensions/webcompat/data/ua_overrides.js
index 1669b437e21a..f1f1e31ca978 100644
--- a/browser/extensions/webcompat/data/ua_overrides.js
+++ b/browser/extensions/webcompat/data/ua_overrides.js
@@ -1379,21 +1379,20 @@ const AVAILABLE_UA_OVERRIDES = [
   },
   {
     /*
-     * Bug 1858664 - UA override to freeze rv segment to 109
+     * Bug 1858664 - UA override for tesco.com
      *
-     * Some sites have issues with a UA string with "rv:" segment
-     * higher than 109, freezing it to 109 fixes the issues.
+     * tesco.com shows access denied with a UA string with "rv:" segment
+     * higher than 109, and version higher than 120.
      */
     id: "bug1858664",
     platform: "all",
-    domain: "Sites with known breakage with rv: segment higher than 109",
+    domain: "tesco.com",
     bug: "1858664",
     config: {
-      matches: [
-        "*://*.tesco.com/*", // #1858664
-      ],
+      matches: ["*://*.tesco.com/*"],
       uaTransformer: originalUA => {
-        return UAHelpers.capRvTo109(originalUA);
+        const cappedRv = UAHelpers.capRvTo109(originalUA);
+        return UAHelpers.capVersionToNumber(cappedRv);
       },
     },
   },
diff --git a/browser/extensions/webcompat/lib/ua_helpers.js b/browser/extensions/webcompat/lib/ua_helpers.js
index 22e0d9fcb325..2cc848f8b005 100644
--- a/browser/extensions/webcompat/lib/ua_helpers.js
+++ b/browser/extensions/webcompat/lib/ua_helpers.js
@@ -79,6 +79,14 @@ var UAHelpers = {
     }
     return originalUA.replace(`rv:${ver[1]}`, "rv:109.0");
   },
+  capVersionToNumber(originalUA, cap = 120) {
+    const ver = originalUA.match(/Firefox\/(\d+\.\d+)/);
+    if (!ver || parseFloat(ver[1]) <= cap) {
+      return originalUA;
+    }
+    const capped = `Firefox/${cap}.0`;
+    return originalUA.replace(`Firefox/${ver[1]}`, capped);
+  },
   getWindowsUA(originalUA) {
     const rv = originalUA.match("rv:[0-9]+.[0-9]+")[0];
     const ver = originalUA.match("Firefox/[0-9]+.[0-9]+")[0];
diff --git a/browser/extensions/webcompat/manifest.json b/browser/extensions/webcompat/manifest.json
index 75a3c45a27f6..0ea6d3aa3527 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": "120.0.0",
+  "version": "120.1.0",
   "browser_specific_settings": {
     "gecko": {
       "id": "webcompat@mozilla.org",