This is an auto-filled bug because media-video/pitivi installs metainfo files into /usr/share/appdata.
The issue was originally discovered on amd64, but it may be reproducible on other arches as well.
If you think that a different summary clarifies the issue better, feel free to change it.
Attached build log and emerge --info.
Created attachment 638154 [details]
build log and emerge --info