Looks like https://pad.lv/1871336 - you can subscribe to this bug it is really it.
Could you please start this application from terminal by
ls -ald ~/.cache
ls -al ~/.cache/blueman-*
killall blueman-tray
rm ~/.cache/blueman-*
blueman-tray
and share the output of this commands? What is your current locale and username on this system? Are they non-english?