Unexpected selection state in custom inspector?

I've built a custom inspector, and it's exhibiting a strange behavior where, when I click off of any element in that inspector to remove focus, it's highlighting all the PrefixLabels in my inspector as if they were "selected" instead.


Any suggestions what might be going on here? I'm at a complete loss. :(

Just maybe you need to fill or choose any options or setting on that custom inspector. Or maybe there something wrong with the code, can you provide some, I love to help since I get help too here.