16.2.5.9 slow export/preview/editing in combination with MBPro (M1 Max) + Apple Pro Display XDR

I've upgraded to the lates C1 version yesterday. Now nearly everything works extremely slow. Export of 600 Canon C-RAWs (25 MB) to 4k resolution jpgs takes more than an hour (previously a couple of minutes). Rotating often shows a 'black' preview or even no smooth experience while finding the right angle. The same is true for every other adjustment. The update of the picture takes multiple seconds. No way to work with this poor performance. 
When I disconnect the MBPro from the XDR display everything behaves fast as expected. 

I hope that this is bug that will be fixed quickly.