install xautomation
killall xbindkeys
Copy paste content from .xbindkeysrc or get your needed mouse button data with xev command and what keyboard buttons you want to press with xbindkeys --multikey.
sudo nano ~/.xbindkeysrc
xbindkeys -f ~/.xbindkeysrc
Start xbindkeys at boot.
Add xbindkeys to ~/.xinitrc
sudo nano ~/.xinitrc
If this didn't work, set /usr/bin/xbindkeys to startup programs/scripts