2.3.0-rc2 and multimaterial issues  

2.3.0-rc2 and multimaterial issues

Hi

tried out the new rc2 and was going to print the popular phone stand, decided to try the multimaterial version, this one:
https://www.prusaprinters.org/prints/40856-phone-stand-multi-material

and with rc2 it initially looks ok but after adjusting the settings like i want it it turns into a single material print and half the print time (12 vs 6h)

what i did is: make sure right print profile is selected (mk3s mmu2s) and 0.20mm speed and prusament pla
then drag over the two stl files.
change colors on extruders so i can more easily find out if i need to swap or not (first is black, second is white) if needed swap the color on the parts to match like i want it.
change both print temp to 220 and max volumetric flow to 11.5 and also enable detect bridging and that's about it.

i usually click on slice a few times when i do this, in the beginning it usually looks ok, i got two different colors but when i have all settings the way i want it, the slicing preview ends up with only a print using extruder 1.

if i do the same steps using same model on 2.2.0 it behaves correctly.