Isn't it a bit odd that the action=unread;all doesn't show read messages that you have marked as unread?
Or it is normal?
/me has never used that function... :-[
Fixed here: https://github.com/emanuele45/Dialogo/commit/c9b36083fbb05f1ef87393381ad3826ff4b8a322
It was an error in parameters order.