Frappe lms app button

Learning
1

I want to add a button to LMS Quiz form


frappe.ui.form.on("LMS Quiz", {
  refresh: function(frm) {
    frm.add_custom_button(__("Upload PDF"), function() {
      frappe.ui.file_manager.show({
        allow_multiple: false,
        
        on_success: function(file) {
          frm.set_value("pdf_file", file.file_url);
          frm.save()
            .then(() => {
              frappe.msgprint(__("PDF has been uploaded and saved."));
            });
        }
      });
    });
  }
});

i added this script as a client script but it doesnt show on the lms app it is visible in the desk app