features window should have desc label selectable (in order for example to be able to select url mentioned there)

don't always show events in systray when notify_on_all_muc_messages is on and trayicon_notification_on_event is off

Make some strings translatable in adhoc commands, Warn user when session id changes in the middle of a session. fixes #3432

use timeout_add_seconds instead of timeout_add (when it's available), more efficient. fixes #3734, #3736