So after a day I give up, it drives me crazy and I cant see a real difference, so I turned it off again…
Here the FP4 changes the direction sometimes, even when auto rotate is switched off.
I had this issue with my FP3. Autorotate off, but still changed to landscape occasionally when placed on a flat surface (table etc). And didn’t change back to portrait unless I close all apps and lock/unlock screen. I’ve changed to FP4 last week, and this one NEVER switches to landscape, even when autorotate is turned on.
I also find - but I guess that’s another topic - the screen reaction very sluggish to touch, compared to my FP3