bug#47581: 27.1; tab-bar missed mouse clicks on MS-Windows

[Juri Linkov]

>> There was a clearly visible indication with raised images
>> on mouse pointer movements over the tab close buttons.
>
> Only on the tab close buttons?  I thought you were talking about the
> button as a whole: those don't react to mouse movements, at least
> here.
>
> Anyway, I've restored the mouse sensitivity of the tab-close buttons.

I confirm that now the tab close buttons react to mouse movements as before,
and also there is no more issue of missed mouse clicks reported by Ioannis.
But tested only on GNU/Linux, I can't confirm for MS-Windows.