fix: don't query iframe document if contentWindow doesn't exist

Author: chrisvxd

src/view/iframe/query-selector-all-iframe.ts

@@ -28,7 +28,9 @@ export default function querySelectorAllIframe(selector: string) {
   const iframePossible = iframes.reduce<HTMLElement[]>(
     (acc, iframe) => [
       ...acc,
-      ...querySelectorAll(iframe.contentWindow!.document, selector),
+      ...(iframe.contentWindow?.document
+        ? querySelectorAll(iframe.contentWindow.document, selector)
+        : []),
     ],
     [],
   );

src/view/use-style-marshal/use-style-marshal.ts

@@ -65,7 +65,9 @@ export default function useStyleMarshal(contextId: ContextId, nonce?: string) {
       getHead(document),
       ...(
         querySelectorAll(document, `[${prefix}-iframe]`) as HTMLIFrameElement[]
-      ).map((iframe) => getHead(iframe.contentWindow!.document)),
+      )
+        .filter((iframe) => iframe.contentWindow?.document)
+        .map((iframe) => getHead(iframe.contentWindow!.document)),
     ];
 
     // Create initial style elements