I was using the material manager fine until I went to make food then came back 1 hour later to this issue occurring. I wanted to make this reply in case it helps narrowing down the issue if it serves any relevance. I’ve been experiencing this for quite some time now. From my knowledge, this issue started happening after the announcement post was made, don’t quote me on that lol;
https://devforum.roblox.com/t/3d-import-recap-mar-apr-2024/2979668