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After doing
sudo pacman -Syumy mouse's primary button (left click) has stopped working properly. When holding the button and moving the mouse sometimes a mouse release gets detected even though i never released the button. Some clicks just don't register.
xev also shows this behaviour.
I've tried downgrading libinput to an earlier version from the pacman archive, but it didn't help.
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Boot some live distro and check how the mouse behaves there.
Check for the events (involutary releases) w/ "evtest"
Try the LTS kernel.
This might be https://www.merriam-webster.com/dictionary/coincidence and the problem w/ the HW
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