Ok, I did not know where to ask this, so I'll post my problem here.
The program stopped working after a shutdown (the PSU got accidentally disconnected) – the application can be launched, but then it hangs at 30% at the loading screen (splashscreen). I suspect this might also have something to do with the fact that the option to keep the database in memory and then save it every now and then was ticked; the database apparently was not saved and therefore is now lost.
How do I solve this problem? Because until I do, I have to use Liferea instead, and this means I can no longer access my starred articles.