welcome to DLC pop-up keeps on re-appearing

@koalicja228  To be clear, after deleting ReticulatedSplinesView, you'd see the pop-up for each pack one more time, since the new file wouldn't contain the data that you've already seen info.  But the pop-ups shouldn't appear the second time you load the game with the new file in place.  Did you ever try loading twice after deleting this file?  I'm not sure from your description.

If you have tested twice with the same new ReticulatedSplinesView file, is OneDrive running on this computer?  It could be downloading an old, corrupt version of the file, or removing it and forcing the game to generate a new one.  That could be the case even if you never use OneDrive yourself.