when I enter the pacmager menu, it is impossible for me to close the options menu window and I have to close pacmager in the system monitor
pamac =! pacman
pacman has no UI, pamac has.
It seems you run Manjaro in Boxes, make sure is not a glitch with the mouse input …
When you open Pamac > Preferences there is an authentication dialog box, then you can change the options and close it. Do you run that VM without password?