looking for conflicting packages...
:: python-protonvpn-nm-lib and protonvpn-cli are in conflict. Remove protonvpn-cli? [y/N] y
:: python-protonvpn-nm-lib and protonvpn-gui are in conflict. Remove protonvpn-gui? [y/N] y
error: failed to prepare transaction (could not satisfy dependencies)
:: removing protonvpn-cli breaks dependency 'protonvpn-cli' required by protonvpn
:: removing protonvpn-gui breaks dependency 'protonvpn-gui' required by protonvpn
-> exit status 1
p.s. btw Is there a way to remove all AUR packages from system at once?
You could check via pacman -Qi and see if it “Depends:” on any other packages or not, if “None” then it should be safe enough to remove. Or also use pactree -r to see what applications might still use the package your searching for. pacman -R to remove just the package, pacman -Rs to remove the package AND it’s dependencies, or pacman -Rns to remove the package, the dependencies, and any config files.