No, they don’t exist. You can’t use them, but I got these:
This error is quite clear: you are using FORM.RUNMODAL somewhere and that is not allowed.
But this error is less clear: It means you are using FORM::"Some Form" somewhere.
The fun part is that if you have the object open and hit F11 to compile and see for errors, the last error does NOT come up. Saving the object with toggle "Compiled"=Yes gives those errors.