Thx Alex, 500ms delay helped. Debug now shows Visible fields in the message window.
Back to original question on how to Toggle READONLY/VISIBLE field with the rule. With one rule, the field only shows (as editable) when the rule fires, and doesn’t show at all when rule doesn’t fire, even the field is listed on the TAB. Do I need to create a 2nd rule with opposite criteria and use ReadOnly fields there, or theres a way to accomplish Toggle with a single rule?