Comment # 3 on bug 951117 from Wolfgang Bauer

(In reply to Jimmy Berry from comment #2)
> If I am not mistake I believe someone indicated that patch2010
> (0001-Fix-QWidget-setWindowRole.patch) was the one supposed to fix this
> behavior, but doesn't seem to in suse.

Yes, the patch is applied since months, and it works as intended AFAICT.
But as it is a patch for Qt5, it only affects Qt5 applications of course (which
already rules out most in your list).

And it only makes the window position being stored/restored by session
management, i.e. windows that were open at logout (or when you manually save
the session) will be restored at the same position at the next login.

kwin itself does not (and never did) remember window positions AFAIK. If you
close an application and open it again, kwin decides on its own where to place
the windows regardless on where they were postioned before.
You can influence the placement via kwin's settings though to a certain degree,
and you can force specific windows to a certain position/size (or even to
remember theposition/size) via "window rules".

Closing as INVALID as I don't see a bug here. Although FEATURE or UPSTREAM
would probably also be fitting...

Feel free to reopen if you disagree, though.

PS: the session management problems regrading KF5 applications should be fixed
already since a while too, see bug#955280.