BuddyPress.org

Im doing some coding where i need an action that fires within the editor’s <form> element from which i can output a hidden field.
I know that i can use this action with the Gutenberg editor:
add_action( 'block_editor_meta_box_hidden_fields', 'add_cat', 10, 1 );

So my question is which editor the “BuddyPress User Blog” is using ?
And if it uses some other editor which action can i then use instead ?