Windows remote desktop - how to untrap keyboard?
Since I had the same problem and read these answers I must add my solution - maybe it helps someone else.
I wanted to press Ctrl+Alt+Pause/Break but accidently hit Press Ctrl+Alt+Home.
I found that this moves the focus out of the maximized window to the title bar and after that Alt+Tab is working.
Think this is slightly more handy ..
When full screen and set active, there is no way to "untrap" keys.
However, based on your comments on the other answer, if you just want a plain keyboard only method of getting out of Remote Desktop, try the following:
This will take you out of full screen mode and "untrap" the keys, meaning you can do Alt+Tab. To get back to full screen mode, simply do the same shortcut.
Before connecting to the remote computer, you can change in the properties (local sources) to never send keyboard shortcuts to the remote pc. By default its set to: Only when in full-screen. When set to local, certain keyboard shortcuts that are different than what you normally use become active.
Alt-tab becomes alt-pageup.
Ctrl-alt-del becomes ctrl-alt-end.
Microsoft documentation about this