>>200
Well, whatever was wrong seems to have fixed itself. My default gui session was set to 'last session' and there weren't any errors in the client.log file. I have 16GB of RAM, but my web browser was eating up quite a bit of it. Maybe that was the issue? Anyway, thank you for the help!

>>206
Hydrus Dev says he uses ToDoList in the Hydrus documentation. https://hydrusnetwork.github.io/hydrus/help/getting_started_installing.html
The link in the docs goes to a 404 page, but the homepage http://www.abstractspoon.com works fine.