App's window moves to initial place after cliking buttons in the app

[cip]

Wine 6 on linux mint 20.1.
After the system upgraded from wine 5 to 6 I noticed this:
1. windows app open -> it's window opens somewhere on the desktop (where it was when it was closed - let's call this 'origin')
2. I move the app's windows somewhere else on the screen -> all ok
3. I click a button or a tab or even select something from the app's menu -> the app's window moves back to the position where it was at step 1 <- not ok!

If I disable "Allow the window manager to control the windows", the app's window doesn't move by itself back to the origin. But then it stays on top of all desktop apps (that's 'normal').

I restored the system back before the wine 6 upgrade (except the home folder - just using default settings in `timeshift`), upgraded everything but the `wine*` packages -> all ok, the app's window doesn't go back to origin.

Upgraded wine 5 to 6 (and nothing else):
wine-stable-amd64/focal 6.0.0~focal-1 amd64 [upgradable from: 5.0.3~focal]
wine-stable-i386/focal 6.0.0~focal-1 i386 [upgradable from: 5.0.3~focal]
wine-stable/focal 6.0.0~focal-1 amd64 [upgradable from: 5.0.3~focal]
winehq-stable/focal 6.0.0~focal-1 amd64 [upgradable from: 5.0.3~focal]

I started the windows app:
- message window: "The wine configuration in /home/myusername/.wine is being updated, please wait..."
- message window: "rundll32.exe - This application could not be started" --- "Do you want info about this issue?" I clicked "No"
But the app starts. No message windows on subsequent runs of the same or other apps.
I do the steps 2 and 3 -> window moves back to origin.

I have 5 windows apps installed, only 2 of them are behaving like that.

For now I restored the system to wine 5 and froze the `wine` package.

[jkfloris]

I have 5 windows apps installed, only 2 of them are behaving like that.

Which Windows programs behave strangely? Do you have the same problem if you install the program in a clean Wineprefix?

[cip]

Installing one of the 2 apps behaving strangely in another wine prefix was the first I tried, forgot to mention.
One the apps doesn't have a demo, can't share that but the other one is free, anyone can try replicate:
- website: http://gal-ana.de/basicmm/en/
- direct downlod link: http://gal-ana.de/basicmm/download/mmanabasic.zip
Install, run, move the window on the desktop, click another tab in the main window (Geometry, View, Calculate, Far Field Plots - see the pic http://gal-ana.de/basicmm/en/view.gif) and the app's window will jump back to the place it started on the screen.

[cip]

I fired up a brand new virtual linux mint 20.1 box, installed wine, installed the above program => same behaviour. At least I know it's not my box or my prefix settings at fault.

[cip]

I ran some more tests in some other virtual boxes [with different window managers]:
1. Ubuntu [Gnome] - no problems
2. Ubuntu Mate [Marco with/without compositor] - same problem
3. Linux Mint Mate [Metacity/Metacity+whatever] - no problem
4. Linux Mint Mate [Compiz] - no problem
5. Linux Mint Mate [Marco/Marco+whatever] - same problem

So far, the issue seems to be connected to the window manager in use, problems are with "Mutter (Muffin)" in Mint Cinnamon and "Marco" in Mint Mate and Ubuntu Mate.