Can I freeze a presentation display while continuing to work on my Mac?

Yes. Stream the desktop you are presenting to the external display, then choose Pause Streaming to keep its current frame visible while you continue working on the source desktop.

In BetterDisplay’s menu, open the source’s Stream Display or Stream Virtual Screen menu and select the projector or external monitor as the target. Full-screen streaming requires Pro and the appropriate macOS screen-capture permission. Ordinary macOS mirroring does not provide this pause option, so use BetterDisplay streaming for this setup.

When the image you want to leave on screen is visible, choose Pause Streaming in that submenu. Choose Unpause Streaming when you are ready to resume live updates. Pausing keeps the current image visible. Stop Streaming ends the presentation. In the ordinary overlay mode, Hide Stream temporarily reveals the receiving desktop underneath.

For keyboard control, assign Pause all streams under Settings > Keyboard > Keyboard Shortcuts… > Full Screen Stream. That shortcut also affects other active streams and PIP windows, so use the individual stream’s menu when you only want to pause one output.

Follow the presentation-freeze tutorial for a harmless Pause/Unpause rehearsal, separate Hide and Stop checks, and targeted cleanup. Test the actual audience output before presenting; pause does not establish a privacy boundary. See Streaming for the controls.