I broke Gallery, how do I fix it? [answered]
Long story short, I found two folders full of thumbnails, ~/.cache/.nemothumbs/raw and ~/.thumbnails/normal. The latter had over 28 thousand files in it, all thumbnails of modRana and Poor Maps map tiles. So I purged it. I also deleted some files from the other folder, thumbnails of pictures I know for 100% I had deleted a long time ago.
Now Gallery shows no pictures and no videos, only ambiences. The files are there but Gallery does not show them. Restarting tracker in Sailfish Utilities has no effect. Nor has taking a new picture in Camera. The new file is created but nit shown in Gallery.
How now, brown cow?
And when I do get it fixed, how do I purge old thumbnails safely?