[apparmor] [Merge] ~talkless/apparmor-profiles:fix-thunderbird-attachements into apparmor-profiles:master

[intrigeri]

Thanks Vincas for the MR & Simon for the review (that will save me quite some time)! I'll look into this soon.
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https://code.launchpad.net/~talkless/apparmor-profiles/+git/apparmor-profiles/+merge/332870
Your team AppArmor Developers is requested to review the proposed merge of ~talkless/apparmor-profiles:fix-thunderbird-attachements into apparmor-profiles:master.