What this guide covers
Screen capture is an explicit permission boundary. The browser shows a picker for a tab, application window or screen; the site cannot silently select an arbitrary application for you. Choosing a narrower source reduces unrelated material in the captured image. A cropped recognition region is not a substitute for choosing the correct sharing source in the first place.
Set it up
Use a supported desktop browser over HTTPS, or the local development origin. Click the sharing control yourself, choose the source and inspect the preview before creating tasks. On operating systems with a separate screen-recording privacy setting, allow your browser there as well. A permission granted to one browser is not automatically granted to another browser or profile.
Check the result
Read the browser sharing indicator and confirm that moving or updating the intended content changes the preview. A black frame can come from protected media or an unavailable application, not an OCR setting. Never bypass a protection or assume that an apparently successful permission dialog guarantees usable frames from every program.
Before you rely on it
Refreshes, browser restarts and stopping the browser sharing indicator can end a capture stream. Saved source names and dimensions help organize tasks but are not reusable permission tokens. Reconnecting a source should always include a preview check, particularly when two windows have similar names or a previous tab has navigated to a different account.
Troubleshooting
For an unavailable source, check operating-system permission, the browser permission dialog and whether the application is still open. Canceling a picker is a normal action and should not require changing unrelated privacy settings. Avoid sharing an entire desktop merely to work around a confusing window name; identify the correct source first.
Product reference
Whole-screen sharing can include popups, messages and windows moved into view. Window or tab sharing is usually easier to reason about, but still review what the source can display during the session. End the stream from the browser indicator or source control when finished, and check that the indicator is gone. When several sources are connected, stop the specific stream you no longer need and verify the remaining source indicators. Removing a task is not the same operation as revoking a browser capture stream.
Screen sharing starts only after your permission. OCR, barcode detection and color processing run locally by default; screenshots are neither uploaded nor saved. Tasks and records stay in your browser.
Further reading
- Choose a recognition region that stays reliable
- Extract subtitles already visible in a video
- Background tabs, minimized windows and floating view