I'm creating an avatar for Spookality, and I've noticed that the button entries in Action Menus appear with a blank icon, are labeled as "Button Text", and seem to be non-functional. Toggles and submenus are fine, as well as the buttons in the GoGoLoco submenu added via VRCFury, so I'm not quite 100% sure is a bug.

I'll leave a couple of buttons on the avatar for now, the ID:

avtr_0ae41d3f-ae4a-437d-b429-4b1dbb217d20

Toggle "a" turns on emission, button "c" is supposed to change its colour.

(if it was changed externally, "b" would change it back to red)