I had a great week. The program can now track the last time you viewed a file.
last viewed time
By default, file viewing statistics are on. You can control how they work and turn them off under options->file viewing statistics and if you like clear all your records under the database menu.
If you have them on, hydrus now records the last time you saw a file in the media viewer and preview viewer. A 'last viewed' here counts with the same rules as recording view time (typically you need to look at the file a few seconds), so if you just scroll through ten files in a second, those won't be recorded as views.