I made a PR to bring back the close button here: https://github.com/sailfishos/sailfish-browser/pull/905
It seems like at first the close button not being interactive was a mistake. All the functionality to close the tab was still there, the toolbar was just set to disabled by the animator and the menu was covering it. It wasn’t a “close menu” button. For the next Sailfish release the button will then be removed, because it isn’t clickable. My PR reverts that and makes it interactive.
Now some bad news, seems like the pullymenu in the tabpage will now also get duplicated by a popupmenu with a “close all tabs” action… Which makes the browser move even further away from Sailfish design guidelines. D: