Not possible to make a Screen Recording in macOS on an iMac. Bug found.
Using an M1 iMac, running macOS Monterey.
According to this document, the screen recording process should be very straightforward.
How to record the screen on your Mac - Apple Support
However, on an M1 desktop computer without a Touch Bar, the "Stop Recording" button disappears after tapping on the record button. In fact, the entire Quicktime application disappears when a recording is started! I'm amazed no one else seems to have reported this bug.
iMac 24″, macOS 12.2