Not being able to edit NSTextField on NSPopover even though Editable behavior is set

Question

I have an application, which open popover with NSTextField. The text field is not editable. Behavior for text field is set to Editable. I still can

Answer 1

Balazs Toth's answer works, but if you're attaching the popover to NSStatusItem.view the status item becomes unresponsive - requiring two clicks to focus.