Screen goes black when plugging a second monitor

Dear all,

-two days ago i did a revert update and it broke my lockscreen, i had a SDDM problem which i tried to fix then los hope and did a new installation.
Now i have weird problem where my screen goes black and flickering light when i plug hdmi of a second monitor.
-a second problem also showed up; when screen turn off after a period automatically i can’t relog; the screen is black and stays that way. the weird about it i still can lock screen by myself and relog so this problem only happens when screen turns off.

i tried reinstalling video-linux and rebooted but still nothing.
i think sddm has a problem and dont know why after this new installation. Now im looking on how to reinstall sddm.

Any help, guidance and links to this problem would be appreciated. Thanks alot.

For your second problem, me and others also experienced it and apparently switching to an old kernel (5.4) solves the issue:

1 Like