4.0 regression: slow to quit

VLC is much slower than before, sometimes even seems to get stuck, while quitting. This occurs even in CLI when there is no video (it's not the X11/GL/Qt lock-up bug).

This consistently occurs after

main libvlc debug: exiting
main libvlc debug: removing all interfaces
main interface debug: removing module "dummy"
main interface debug: removing module "xcb_hotkeys"
main interface debug: removing module "hotkeys"
main interface debug: removing module "dbus"
main keystore debug: removing module "memory"

and before

main input debug: destroying input for ...
main audio output debug: removing module "pulse"

So it's either the key store or something after it, but before removing the input and the audio output. Most likely, it is the input thread (the destroying input message is only output after the input thread has terminated).