Quang, there may be a workaround. If you are able to use a regular keyboard, you could try to hold the Alt key there, click anywhere on Onboard and drag it away from the top. This should snap it out of the maximisation.
Quang, there may be a workaround. If you are able to use a regular keyboard, you could try to hold the Alt key there, click anywhere on Onboard and drag it away from the top. This should snap it out of the maximisation.