Control: reassign -1 thunderbird Reassigning to thunderbird, as it ships it's AppArmor profile itself.
We have this rule there: owner /run/user/[0-9]*/dconf/user rw,But it it does not handle the case when parent dir is missing. It does not reproduce in my KDE desktop. Maybe you use some minimal desktop where Thunderbird is the first that deals with that dconf stuff?
Anyhow, we should update thunderbird profile.