All textures constantly changes "Texture Type" to "Advanced" leaving weird light issues

I imported a new sprite for a button, chose Texture Type "Advanced", customized it, clicked apply.

For some reason that caused all textures in my project to also switch to "Advanced", even though I have only used it for this one sprite. All of the .meta files connected to the textures/sprites in the whole project are being updated as well. That causes amoing other things, the SkyboxProbe-0 to be a lot darker and the colors in the scene is changed because of this. Once I try to revert the SkyboxProbe Texture Type to "Cubemap "it immediately changes back to "Advanced".

If I close Unity, delete the Library folder in my project, reset the .meta files for the textures in git, and open Unity again, the problem is solved. However as soon as I switch platform, the problem reappears. And all the .meta files are changed again, the scene is dark, etc.

What's strange is that since this bug is introduced, going back in git history and checking out a commit before this problem occured, is not helping. The problem is now somehow connected to the Unity editor and not the project files itself. Once my colleague checked out the commit that caused all this, the same happens for him.

Anyone else that has experienced a similar thing?
Is there some settings saved by unity that we might not have under version control?
Any leads would be greatly appreciated!