Fix multi-webview browser capture prep

packages/desktop/src/features/browser-automation/service.test.ts

@@ -55,6 +55,7 @@ class FakeTab implements TabContents {
   public captureThrows = false;
   public deferCaptures = false;
   public prepareNeverAcks = false;
+  public fullPageScreenshotThrows = false;
   public layoutMetrics = {
     cssLayoutViewport: { clientWidth: 390, clientHeight: 844 },
     cssContentSize: { width: 390, height: 1200 },
@@ -184,6 +185,9 @@ class FakeTab implements TabContents {
       return this.layoutMetrics;
     }
     if (command === "Page.captureScreenshot") {
+      if (this.fullPageScreenshotThrows) {
+        throw new Error("UnknownVizError");
+      }
       return { data: this.fullPageScreenshotData };
     }
     if (command === "DOM.getDocument") {
@@ -959,7 +963,7 @@ describe("executeAutomationCommand", () => {
     }
   });
 
-  test("screenshot restores capture preparation when viewport capture fails", async () => {
+  test("screenshot returns no-frame and restores capture preparation when viewport capture throws", async () => {
     const browser = new BrowserAutomationHarness();
     browser.tab.captureThrows = true;
 
@@ -968,7 +972,15 @@ describe("executeAutomationCommand", () => {
         command: "screenshot",
         args: { browserId: BROWSER_A },
       }),
-    ).rejects.toThrow("capture failed");
+    ).resolves.toEqual({
+      requestId: "req-screenshot",
+      ok: false,
+      error: {
+        code: "screenshot_no_frame",
+        message: "The browser tab has no painted frame. Focus the tab in the app, then try again.",
+        retryable: false,
+      },
+    });
 
     expect(browser.tab.actions).toEqual([
       "prepare",
@@ -1135,6 +1147,35 @@ describe("executeAutomationCommand", () => {
     ]);
   });
 
+  test("screenshot with fullPage returns no-frame when CDP capture throws", async () => {
+    const browser = new BrowserAutomationHarness();
+    browser.tab.fullPageScreenshotThrows = true;
+
+    const result = await browser.execute({
+      command: "screenshot",
+      args: { browserId: BROWSER_A, fullPage: true },
+    });
+
+    expect(result).toEqual({
+      requestId: "req-screenshot",
+      ok: false,
+      error: {
+        code: "screenshot_no_frame",
+        message: "The browser tab has no painted frame. Focus the tab in the app, then try again.",
+        retryable: false,
+      },
+    });
+    expect(browser.tab.actions).toEqual([
+      "prepare",
+      "background:false",
+      "invalidate",
+      "debug:Page.getLayoutMetrics",
+      "debug:Page.captureScreenshot",
+      "restore:capture-1",
+      "background:true",
+    ]);
+  });
+
   test("upload resolves workspace files before setting them on the file input", async () => {
     const browser = new BrowserAutomationHarness();
     browser.tab.snapshotElements = [

packages/desktop/src/features/browser-automation/service.ts

@@ -149,6 +149,17 @@ async function restorePixelCapture(
   }
 }
 
+async function capturePreparedPixelFrame<T>(capture: () => Promise<T>): Promise<T> {
+  try {
+    return await withPixelCaptureTimeout(capture());
+  } catch (error) {
+    if (isScreenshotNoFrameError(error)) {
+      throw error;
+    }
+    throw new ScreenshotNoFrameError();
+  }
+}
+
 async function runPreparedPixelCapture<T>(
   contents: TabContents,
   capture: () => Promise<T>,
@@ -163,7 +174,7 @@ async function runPreparedPixelCapture<T>(
       preparation = await prepareForPixelCapture(contents);
       contents.setBackgroundThrottling(false);
       contents.invalidate();
-      return await withPixelCaptureTimeout(capture());
+      return await capturePreparedPixelFrame(capture);
     } finally {
       try {
         if (preparation) {