From 464a570201e0ba4b93f5822122bdd354465b7ad0 Mon Sep 17 00:00:00 2001
From: sal <sal@salmutt.dev>
Date: Wed, 4 Mar 2026 22:03:12 -0600
Subject: [PATCH] Fix Intl.DateTimeFormat cross-compartment crash and
 Connection API robustness

OrigDateTimeFormat constructor called inside exportFunction callback failed
in Firefox compartment boundary. Moved construction to content-script-scope
helper. Also added addEventListener/removeEventListener to Connection override
to prevent crashes in real-time apps like Discord.
---
 CHANGELOG.md  |  5 +++++
 inject.js     | 22 +++++++++++++++-------
 manifest.json |  2 +-
 3 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e495777..b796f60 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Changelog
 
+## 0.5.2
+
+- Fixed Discord crash caused by Intl.DateTimeFormat cross-compartment constructor failure
+- Fixed Connection API override missing addEventListener (could crash real-time apps)
+
 ## 0.5.1
 
 - Fixed Discord and other complex web apps crashing due to DOM dimension noise
diff --git a/inject.js b/inject.js
index e1360e5..9e7396d 100644
--- a/inject.js
+++ b/inject.js
@@ -247,8 +247,12 @@
             effectiveType: "4g",
             downlink: 10,
             rtt: 50,
-            saveData: false
-          }, pageWindow);
+            saveData: false,
+            addEventListener: function() {},
+            removeEventListener: function() {},
+            dispatchEvent: function() { return true; },
+            onchange: null
+          }, pageWindow, { cloneFunctions: true });
         }, pageWindow),
         configurable: true,
         enumerable: true
@@ -330,10 +334,11 @@
 
     const OrigDateTimeFormat = window.Intl.DateTimeFormat;
 
-    // Wrap the Intl.DateTimeFormat constructor to inject spoofed timezone
-    // when no explicit timeZone is provided. This ensures resolvedOptions()
-    // returns the spoofed timezone and all formatting uses it.
-    const wrappedDTF = exportFunction(function(locales, options) {
+    // Wrap the Intl.DateTimeFormat constructor to inject spoofed timezone.
+    // The wrapper creates the real instance in the content script scope
+    // (where OrigDateTimeFormat is a valid constructor) then returns it.
+    // Using a helper avoids cross-compartment constructor failures.
+    function createDateTimeFormat(locales, options) {
       let opts;
       if (options) {
         try { opts = JSON.parse(JSON.stringify(options)); } catch(e) { opts = {}; }
@@ -341,8 +346,11 @@
         opts = {};
       }
       if (!opts.timeZone) opts.timeZone = tzName;
-      // Support both `new Intl.DateTimeFormat()` and `Intl.DateTimeFormat()`
       return new OrigDateTimeFormat(locales, opts);
+    }
+
+    const wrappedDTF = exportFunction(function(locales, options) {
+      return createDateTimeFormat(locales, options);
     }, pageWindow);
 
     try {
diff --git a/manifest.json b/manifest.json
index 7bb1e0e..a2049b1 100644
--- a/manifest.json
+++ b/manifest.json
@@ -1,7 +1,7 @@
 {
   "manifest_version": 2,
   "name": "ContainSite",
-  "version": "0.5.1",
+  "version": "0.5.2",
   "description": "Per-container fingerprint isolation — each container gets its own device identity",
   "permissions": [
     "contextualIdentities",