Several graphical issues since update to Plasma 6

I’ve got several graphical issues since updating my Arch system to Plasma 6:

  1. Notifications appearing in the middle of the screen instead of the bottom-right corner

  2. When moving windows, the “hitboxes” are at a different position than displayed:
    Screenshot_20240308_051955

Is there any way to fix this?
Thanks and regards

Regarding question one, does navigating to System Settings → Notifications and re-specifying the notification popup location make any difference?

Thanks, but unfortunately that didn’t work