BUG? Unexpected detail view colours when in layout mode new in R7


I just opend an older file which worked a few month ago with R6 and R7.
Now (7.9.21222.15001, 2021-08-10) I see a change how colours/shadow intensity differs between layout mode and detail view mode:
Inside detail view:

Outside detail view (Layout):

In R6 (6.34.21034.7001, 03.02.2021) the problem does not occour.
It’s kind of unexpected when the prints look much darker than in the model view before and hard to manage!

Any advise - maybe I missed some switch somewhere!?