It doesnt help in my caqse, theres always 1/3 of the screen with squashed liveview with about 5:2 aspect ratio and rest of the view is random lines .
BUTI discovered something...

To record longer in 2.8k and 3K modes go to expsure ML menu and set global draw to quickreview, and some magic will happen, i managed to get over 2 minutes in 3K mode.
Danne is it possible to expand this mode to 3.5k ? Maybe it will work ? Cause if i can get over 2 minutes in 3K ? I got orange icon and could go on and on.
3000x1276 and no pink frames, its amazing cause i thought that 2.8k is absolute limit but here it records without problem when i enable quickreview.
I know theres 4K but its different than 3k crop, cause this 4K is in 8fps only for me unlike 3k.
Ah so the 3K is in 20fps , can it be in 24 ? Theres sudden drop to 20fps when above 2800 , when i set 25fps in 3k mode then it drops to 2800 as well.Considering its quite stable for over 2 minutes, can we go higher with fps above 3k mode ? Its not like im getting only few seconds, its long and stable.