and that is how it works in my later Build 946 64-bit Donor PortableImplemented: Tab can be moved per drag&drop to other panel if on drop the Ctrl key is pressed
But I would like to suggest adding another option: that would allow users to outright choose the default behavior without the Control key being pushed down i.e. if a Tab should be copied or moved when it is dragged and dropped to the opposite Panel with usage of merely the Left Mouse Button
I personally 99/100 times need to move a Tab and not merely copy it - thus until that update I was being forced to perform an aftermath cleanup, often prolonged due to a Tab having been locked (i.e. had to deal also with a pop-up to allow closure of the leftover / original). Now I can use the the CTRL for averting of that step - but I often operate when laying down on a bad, thus with a remote mini-keyboard by my side but not in my hands, like it is then in case of the mouse which is the go-to input device. And an ability to operate with just a mouse is very handy for people with certain physical disabilities