Can't quit some apps entirely

[sauntor]

What Happened?

Some apps leaves some background processes after quit/exit, (Steam, for example).

Steps to Reproduce

Take Steam for example)

1. install Steam: sudo apt install steam
2. launch Steam and login
3. click X(close button on the top right corner) or Steam ->Exit
4. open terminal, and run ps ax | grep steam
5. then, there will be some output lines like the following:

   2156 ?        S      0:00 sh -c steam-runtime-launcher-service --alongside-steam
   2158 ?        Sl     0:00 steam-runtime-launcher-service --alongside-steam

Expected Behavior

No process left after quit the app.

OS Version

7.x (Horus)

Software Version

Latest release (I have run all updates)

Log Output

No response

Hardware Info

No response

[sauntor]

There's also an extra problem:
Some apps which stays in background after close, can not reopen the main window by click the desktop icon from the menu, i.e. QQ (install via flatpak install com.qq.QQ or download it from https://im.qq.com/linuxqq/index.shtml, launch it, login, then close the main window, finally re-launch it from menu)

[tintou]

This is an issue with the apps, please fill an issue to the apps upstream.

[sauntor]

This is an issue with the apps, please fill an issue to the apps upstream.

But it works perfectly on ubuntu and openSUSE, no matter installed via deb or flatpak. It may be caused by the same problem as mentioned in the top section.