I was building a folder with extra large custom icon shortcuts to all of my games, because why not, and everything was going well. But when I was halfway through, suddenly icons I had already set started randomly showing up as medium size.
Rebuilding the icon cache and restarting the computer does not seem to fix the problem, but it does cause which icons are messed up to randomly change; fixing some and messing up others.
I also attempted to increase my icon cache size, and it did not seem to do anything.
Here's an image of the problem in-case my description was unclear:
And an example of the icons randomly changing after rebuilding the icon cache: