Details View not working correctly on a custom Editor Utility Widget


I’m working on an Editor Utility Widget and I’m having some weird issues when trying to add a Details View. There’s something very broken with the categories. Here’s an example I made in a new project and a fresh install of 4.26.2:

I set the category to 1 and it shows everthing in 1 and 2. So I moved the variable D to a new category 3, and now if I set the category to 3 it draws 1, 2, and 3.

Has anyone else seen this problem or should I hire an exorcist?