I have a student using Photoshop Elements 2020 on a Mac running Big Sur. She cannot get the keyboard command to hide the current selection (Cmnd "H") to work. I am using the same setup and this keyboard command works for me.
What might she have done to lose this keyboard command?
On my windows 10 machine I use CTRL+D to deselect an outline selection. Have your pupil try CMHD+D.
On the Select menu in Editor, is there a shortcut listed for "Deselect?"
I don't' want to deselect. CTRL+D will lose the selection. Ctrl+H just hides the crawling ants of the sekection. It is often easier to work with a selection if the crawling ants are hidden.
If she goes to View>Selection is the Cmd H shortcut listed?
This time I was able to use CTRL/CMND+H. It gave me several options which included "hide extras". This was the choice which hid the crawling ants without losing the selection.