Deleting the .local/share/Icedrive folder fixed this in the past, but doesn’t work now. I even timeshifted the machine back to before I installed Icedrive, but I get the same results on reinstall. I’m not getting any errors, so I’m not sure what else to try. Googling reveals very little on this issue.
Are you running the appimage version or the CLI version? It’s possibly an OpenGL which we’re investigating. Would it be possible for you to submit a support ticket via Login - Icedrive and attach some screenshots as you have here to illustrate the issue and I will forward onto our development team?
FWIW, I’m still working with support on this, but I’ve found on my setup at least that logging out of the client using the context menu and then running the client again gives me the window back and lets me log in again. I’m back to the black window again as soon as I shut the client down again, but it’s a workaround for now for each session.