I am the most, very most stupid man in the world....
I cannot believe it myself...
I was following Jacek's tip and opened Screen prefs. Okay:
Ambient - RadeonX1650 24Bit 1920 x 1080.
BUT: After I wanted to edit that, there were only modes for the HD5450!!! :((
First I thought: ohhhh, there went somethong wrong. MorphOS does not correctly recognize my gfx board any longer...and the second thought was: Is the X1650 actually installed...???
NOOO!
Some weeks ago I did some tests with different gfx boards (HD5450, X1650, X1950 Pro/XT) and finally - please do not ask me why - I did not install again the X1650, which was the goal (watching YT videos!!!!), but the HD5450.
So embarrassing!
Please apologize!
The best: Not only YT works with Wayfarer, everything is so much faster.
MorphOS developer: PLease support more current gfx boards. It is such a difference.
AmigaOne X5000 @ 2GHz / 4GB RAM / Radeon X1650 / AmigaOS 4.1 Final Edition / MorphOS 3.17
Amiga1200 / Blizzard 1230 IV PiStorm32-lite / 128 MB RAM / AmigaOS 3.9