Allow Button script to show a "result message" which can be copied

If a Button script throws an error, the Error.message gets shown in the Button’s “result popup”.

It would be useful if a Button script could also display an arbitrary message in the “result popup”:

Right now the only way to do something like this seems to be with console.log, which is not a great solution.

Also it seems not possible to select and copy text from the Button “result popup”, because it just closes as soon as you click on it.

Use case: I’m using a Button script to expose a password field (normally hidden).
Yes, it’s a workaround for not having entity-based permissions.