Menu options are not executed on Alt+letter
Start MuseScore 4, Hold down Alt+F to access the File menu, then press O to open a file.
The File menu opens, the Open option is selected, but does not get executed. This is not what is expected, as a normal UI would execute the command right away the letter is pressed on the keyboard.
As a workaround you can press Enter after pressing O, but it requires an extra keypress.