In a channel chat userlist the automatic cleanup function doesn't work properly.

reproduce:
1. open the 'clean channel user list' window
2. deselect the 'remove sharing users that have been offline' option
3. hit apply
4. it still removes the users that have been offline and sharing
5. and when repeated with the 'apply continously' off
6. hit apply
7. all the 'offline non-sharing users' comeback in an instance from the other users/peers in the chat.

expected results:
the options buttons work as selected.
Offline sharing users should be able to stay in the room
iaw. sharing offline users should not be removed unless set otherwise
Offline users should never come back into the userlist except when online again and behave as selected
iaw. when removed after say 120 days they stay offline forever until the user/id is online again.

feature request:
make the removal offline (non-)sharing users options a channel owner setting for
the complete room to reduce bandwidth usage and keep shares in the room if a user is never seen again.
This would also apply to forum messages, so you can keep all messages in the room (sharing users).

system:
Linux Fedora 25 64bit Gnome
v 2.52-a2 linux 64bit

Keep up the good work :)