There is no dependable “hide this one window from Zoom” switch on macOS 15 when you share an entire display. The capture source is the display. A hidden app may be out of sight now, but a notification, app switch, or window animation can still reveal it later.
Choose a safer sharing boundary
| What you need to show | Safer choice | Trade-off |
|---|---|---|
| One document or app | Share that window | Switching to another window is not visible |
| Several related apps | Use a separate desktop/display | Requires setup and attention |
| A demo with secrets nearby | Fullscreen a dedicated browser profile | Less flexible during questions |
The biggest practical improvement is to share a specific window, not “Screen 1”. Before joining, close unrelated tabs, pause notifications, and move password managers, messaging apps, and terminals with credentials to another display.
“Do Not Disturb” reduces interruptions; it does not redact content already visible on the shared display.
A pre-call routine worth keeping
- Open the exact window you intend to share and resize it before the meeting.
- Enable Focus / Do Not Disturb and quit apps that show previews.
- Check browser profile, bookmarks bar, shell prompt, and any visible customer identifiers.
- Start sharing, then use the meeting app's preview to confirm the selected source.
For a repeatable demo, use a dedicated macOS user or a clean browser profile with fixture data. It sounds excessive until the first time a private Slack preview appears during a recording. Privacy in screen sharing is mainly a choice of capture boundary, not a window-hiding trick.