Category tabs sometimes appear as solid color instead of their icons.

1. I don't have a resource pack or behavior package installed
2. I don't know the cause of it, but I've encountered it several times while playing
3. If you are in too much of a hurry to interact with the backpack, this bug may occur
4. This bug: Closing the backpack and then opening it will return to normal

This bug is so rare that I can't reproduce it again