In L4 A8, I set up a workspace that included a few different windows (am I allowed to use that word when speaking of Macs?), each with a number of resources. Each resource has a tab and I was able to arrange them in a variety of ways including in a straight line row across the top.
I just installed L4 A9 and one of the options seems to have changed. I floated one of the resources, but when I tried to return it to the row of tabs, it would not let me. I can split the window in a number of different ways, but it won't let me line it up with the other tabs back in the straight row. It also means I can't change the order of the tabs because as soon as I try to move a tab, it tries to become a smaller window within the larger window.