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I was just surfing on web, and my laptop turned off because i forgot to plug charger, after I turned on laptop, and tried to log in, It just sent me back to login again, I can login using tty2, tty3 etc. and I can login using different Desktop Environment. Im using i3, So i dont know what is the problem with i3, I was using it just fine whole day, didnt change anything. Why is everything else working except i3. I ran pacman -Syu and still same mistake. Tried login as root on i3 aswell but its not working either.
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Read your Xorg log.
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I can login using different Desktop Environment
Unless "different Desktop Environment" refers to some wayland session, Xorg is less likely the problem.
Check your journal and coredumpctl.
What might have happened is an update that didn't get sync'd to the disc (because of the hard reset) - if the package is listed up-to-date you won't fix that w/ a global update.
Run "pacman -Qkk" to see which packages might have broken files and re-install them.
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