Are you taking about tab center? That thingy had a number of issues last I checked, I especially remember there was something weird about the layout of it. I th

Are you taking about tab center? That thingy had a number of issues last I checked, I especially remember there was something weird about the layout of it. I think it extended all the way up on the side of the menu bar. This looked weird to me (and I think UI is overrated) and makes the toolbars slide when I open/close the tab drawer. I'd recommend using one of the extensions instead.