[PM-1407] Improve iframe sandbox detection (#5976)

* improve iframe sandbox detection

* code cleanup

Co-authored-by: Cesar Gonzalez <cesar.a.gonzalezcs@gmail.com>

* update autofill v1 logic as well

---------

Co-authored-by: Cesar Gonzalez <cesar.a.gonzalezcs@gmail.com>

apps/browser/src/autofill/content/autofill.js

@@ -768,8 +768,16 @@
 
       // Detect if within an iframe, and the iframe is sandboxed
       function isSandboxed() {
-          // self.origin is 'null' if inside a frame with sandboxed csp or iframe tag
-          return self.origin == null || self.origin === 'null';
+        // self.origin is 'null' if inside a frame with sandboxed csp or iframe tag
+        if (String(self.origin).toLowerCase() === "null") {
+          return true;
+        }
+
+        if (window.frameElement?.hasAttribute("sandbox")) {
+          return true;
+        }
+
+        return location.hostname === "";
       }
 
       function doFill(fillScript) {

apps/browser/src/autofill/content/autofillv2.ts

@@ -849,7 +849,15 @@ function fill(document: Document, fillScript: AutofillScript) {
   // Detect if within an iframe, and the iframe is sandboxed
   function isSandboxed() {
     // self.origin is 'null' if inside a frame with sandboxed csp or iframe tag
-    return self.origin == null || self.origin === "null";
+    if (String(self.origin).toLowerCase() === "null") {
+      return true;
+    }
+
+    if (window.frameElement?.hasAttribute("sandbox")) {
+      return true;
+    }
+
+    return location.hostname === "";
   }
 
   function doFill(fillScript: AutofillScript) {