fix: prevent mem leaks by removing unloaded iframes from map

Author: megboehlert

.changeset/shy-carrots-deny.md

@@ -0,0 +1,5 @@
+---
+"rrweb": patch
+---
+
+fix potential mem leaks by deleting unloaded iframes from crossOriginIframeMap

packages/rrweb/src/record/iframe-manager.ts

@@ -77,12 +77,16 @@ export class IframeManager {
     });
 
     // Receive messages (events) coming from cross-origin iframes that are nested in this same-origin iframe.
-    if (this.recordCrossOriginIframes)
+    if (this.recordCrossOriginIframes) {
       iframeEl.contentWindow?.addEventListener(
         'message',
         this.handleMessage.bind(this),
       );
 
+      iframeEl.contentWindow?.addEventListener('pagehide', () => {
+        this.crossOriginIframeMap.delete(iframeEl.contentWindow!);
+      });
+    }
     this.loadListener?.(iframeEl);
 
     if (