Styles for Parts are not loaded when opening an existing file

I have quite some Style changes for my parts, and it is a bit annoying that every time, I reopen a score, the style is not properly loaded. I always have to do a change in the style and revert it in order to load all the style details - and I need to to this for every part.

How to reproduce:
1. Having an existing score with 1 or more parts (in my case the partitur and the parts have different styles)
2. I open the file, and the my parts are messed up (see screenshot: the part usually fits into one page)
3. I go to the styles and do simply one change and revert it again (see screenshot: now the part fits into the page as intended)

See also attached the file I used for the screenshots.

Used version:
OS: Windows 10 Version 2009, Arch.: x86_64, MuseScore version (64-bit): 4.0.1-230121751, revision: 9b70a8c