Error message when leaving DoomBuilder open for some time

[luish199711]

I have received this error message when setting up the game configurations on Ultimate Doom Builder. I have not opened up or created a map. I did have the latest version of Slade open as I was doing some tests on some mod in development.

The error in question
Object reference not set to an instance of an object.
at Codelmp.DoomBuilder.Config.ConfigurationInfo.Finalize() in c:\build\UltimateDoomBuilder\Source\Core\Config\ConfigurationInfo.cs:line 244

At the time of writing this message, the error window is not responding and froze.