The _o_ENABLE BUTTON command is declared obsolete in 4D beginning with version 12 and is kept only for compatibility reasons. Its overall scope, which includes all instances of the designated variable and not only those of the current form, does not correspond to those of the "Object (Forms)" command theme.
_o_ENABLE BUTTON and _o_DISABLE BUTTON can be replaced favorably by the OBJECT SET ENABLED and OBJECT Get enabled commands.