[fritsch]

Those with the artefact problem, can you please test the following builds:

1002b: Generic - same as #0813
1002c: Generic - 1002b + PR14291
1002d: Generic - 1002c + PR14282
1002e: Generic - 1002d + PR14295

1002b should not have the artefact issue, while 1002e should have the artefact issue. I'm not expecting c & d to have it, but who knows for sure so please test them too.

Assuming the issue is confirmed as starting with 1002e then I might try and narrow it down to the specific commit with additional test builds.

Edit: We still need a debug log from an affected build which may reveal some specific GL/mesa behaviour that is hardware dependent.

I didnt have time to do all of them, bu I can confirm D does not have artifacts for me (asus chromebox 2014) 

Do you have custom configured OVERSCAN values? E.g. in kodi's gui calibration? Can you reset them please?