Following this other question I put this in my .xsession file
date -I > /tmp/xsession_started
xmodmap -e "pointer = 3 2 1" &> /tmp/mouser.log
I can see the xsession_started file is created successfully:
cat /tmp/xsession_started
2020-07-29
And the xmodmap ran and left a log:
cat /tmp/mouser.log
Warning: Only changing the first 3 of 10 buttons.
Yet, my mouse is still right handed (the xmodmap should have swapped the buttons out and made it a lefty).
So what is going on here? Is the environment somehow 'before' my actual xsession?
My desktop environment happens to be LXQt this morning, but the same happens when I login to others as well.
EDIT:
Actually KDE and GNOME respect the .xsession setting, it appears to be the 'lesser' environments like LXQT and LXDE, etc. that don't.
xmodmap -e "pointer = 3 2 1"work in the first place if you try it in your X session? If yes, can you try a sleep? I.e.,sleep 3; xmodmap -e "pointer = 3 2 1" &> /tmp/mouser.log. – Quasímodo Jul 29 '20 at 14:00