Woah, do you mean... are you disabling the STM component, gameobject, or the mesh renderer itself? If it's the actual mesh renderer, I probably just have some code to make sure it's active, and I hope the other things work correctly... If not, I'll for sure have to give this a peek soon.
Found why it rendered when disabled, I used Rebuild AFTER I disabled the STM - component... Which I guess updates the mesh renderer? EDIT: removed Rebuild and did stm.text = "test" which even if the component is disabled renders the text!