Since upgrading to 4.0.0rc4, I'm getting frequent crashes with the message
InvalidOperationException: Added item does not appear at given index '0'.
Generally, this happens when I'm refreshing or adding a ROM directory. This happened most recently on
Commodore - Amiga CD - Datfile (350) (2019-03-02 12-39-06).dat from redump.org.
I clicked on "Yes" to send the error report, but I'm not sure if it was transmitted or not.