In 30-40% cases instead of clicking a tab I close it, because (x) suddenly appear.Either option is needed or some logic, .e.g when width is minimized do not show close button (x).
I vote against this, or, at least, for an option to show/not show "close" button.It is always easy to do mouse middle-click to close tab. But, in vertical mode it really comfortable to squeeze size to a minimum (only icons). After that the (x) button...
