Guard emulateFocusedPage calls

Author: CVSz

src/McpContext.ts

@@ -344,20 +344,28 @@ export class McpContext implements Context {
     return this.#selectedPage === page;
   }
 
+  #maybeEmulateFocusedPage(page: Page, focused: boolean): void {
+    const maybeEmulate = (
+      page as Page & { emulateFocusedPage?: (focused: boolean) => Promise<void> }
+    ).emulateFocusedPage;
+    if (!maybeEmulate) {
+      return;
+    }
+    void maybeEmulate.call(page, focused).catch(error => {
+      this.logger('Error toggling focused page emulation', error);
+    });
+  }
+
   selectPage(newPage: Page): void {
     const oldPage = this.#selectedPage;
     if (oldPage) {
       oldPage.off('dialog', this.#dialogHandler);
-      void oldPage.emulateFocusedPage(false).catch(error => {
-        this.logger('Error turning off focused page emulation', error);
-      });
+      this.#maybeEmulateFocusedPage(oldPage, false);
     }
     this.#selectedPage = newPage;
     newPage.on('dialog', this.#dialogHandler);
     this.#updateSelectedPageTimeouts();
-    void newPage.emulateFocusedPage(true).catch(error => {
-      this.logger('Error turning on focused page emulation', error);
-    });
+    this.#maybeEmulateFocusedPage(newPage, true);
   }
 
   #updateSelectedPageTimeouts() {