Was window screen sharing disabled by Apple? I suddenly cannot choose which windows to share on any interactive whiteboard using HDMI connection. Only full screen reflection is allowed, which means I cannot use Keynote in presenter mode and see my notes!
MacBook Pro 14″, macOS 15.6
> Only full screen reflection is allowed, which means I cannot use Keynote in presenter mode and see my notes!
There has never been an option to display a specific window to an external display (which is what the HDMI device will appear as).
Your options are to mirror your MacBook Pro's screen, or extend the desktop.
If you extend the desktop then you can move specific windows into the extended space, to have them show on the extended display. Also, Keynote will recognize the external display and, by default, use it for the presentation, reserving the built-in screen for presenter notes. This sounds like what you want.
Use System Settings -> Displays to setup an extended desktop and see if that fixes your issue.
> Only full screen reflection is allowed, which means I cannot use Keynote in presenter mode and see my notes!
There has never been an option to display a specific window to an external display (which is what the HDMI device will appear as).
Your options are to mirror your MacBook Pro's screen, or extend the desktop.
If you extend the desktop then you can move specific windows into the extended space, to have them show on the extended display. Also, Keynote will recognize the external display and, by default, use it for the presentation, reserving the built-in screen for presenter notes. This sounds like what you want.
Use System Settings -> Displays to setup an extended desktop and see if that fixes your issue.
I do not remember mirroring specific windows ever being a feature. It sounds like what you are looking for is extended desktop mode, with your slides being shown on the HDMI display and your notes being shown on the built-in one. That might require dragging windows to the desired screen(s).
Note that there may be some interaction between the setting for “Displays Have Separate Spaces” and the options available.
Play a presentation on a separate display in Keynote on Mac - Apple Support
"To prevent viewers from seeing the presenter display on the connected displays, turn mirroring off."
[When you Play > In Fullscreen] "By default, the slideshow appears on one of the external displays, and the presenter display appears on your Mac and any other connected displays."
Extend or mirror your Mac desktop across multiple displays - Apple Support
This is not the normal dialog that appears when you're using a direct-attached display.
This is part of AirPlay, where you're steaming the video over the network. That does allow for single-window streaming, but then your display will be connected over the network, not via an HDMI cable, which is why the original responses didn't match your expectations.
So the bigger question is how you're connecting your display to your Mac?
Here is what I used to get and was working perfectly. I could play Keynote presentation in separate window, share that window only plus any others I needed like a browser or any other app. Now it is still there but when I choose this middle option, the „add this screen“ appears greyed out ☹️
Thank you for your response.
In this case I cannot mirror anything other than the presentation and I need to share a browser window to open links.
Thanks for your response…
See my reply below, this IS actually a recent feature that still exists but is not working as it was a couple of weeks ago.
Cannot select specific windows for screen sharing via HDMI
