Thumbnail cache cleanup

[Nate Graham]

Howdy folks!

I don't see anything in the thumbnail spec[1] about thumbnail cleanup policy, and as a result, the thumbnail cache's size is unbounded and can become quite large for users with a lot of images. Should we add some kind of cleanup recommendation to the spec, or rely on distros to implement their own preferred cleanup method and frequency?

Nate Graham

[1] https://specifications.freedesktop.org/thumbnail-spec/thumbnail-spec-latest.html