Regression, double-clicking titlebar to restore from maximized state does not always restore the correct former position

I hope that I didn't create a ticket about that before already.
I am pretty sure that it regressed by some of the work towards the WindowSnapping during 0.4.15-dev'ing.

I can properly double-click a titlebar, which will bring a windowed window into maximized state
But when I double-click the maximized Windows titlebar again, I would expect it to return into windowed mode with its former size and position

This is what Windows does, but ReactOS fails with that currently.

It still worked fine in 0.4.14-release-124-g4962530
reactos-bootcd-0.4.16-dev-116-g1643793-x86-gcc-lin-dbg_affected.webm is affected.

Nothing is logged, therefore I left aside the logfile here.

There is one important thing to add. It isn't like it would never work in the affected builds. It often works, but when retrying the procedure several times in a row, at some point it will stop working!!! To me it seems, as if it properly restores the "windowed mode" then, but fails to restore the proper former position of the Window.