Each tab is a checkbox (selected or not), an input field, a drag handle for the page and a drag handle for the window, depending on how fast you start dragging and in which direction. If you hover it it shows a set of buttons, but if it’s focused the buttons disappear entirely and can’t be dragged or closed at all.

They hid a few buttons in a tiny dropdown that appears on hover; They kept a completely useless clickable lock icon in the middle-ish of field so now there’s a little chance that, while trying to do any of the above, you’ll end up with a popup that you have to close instead.