New tabs should always open to the immediate right of the current tab. And now they will. Usually when I open new tabs, it's not because a lightning bolt struck, and I must switch from my current activity to a new and different one. Most of the time the new tab is directly related to what I'm currently doing, so when Firefox (or a Chromium-based browser) opens tabs at the end of 50 tabs, they're almost guaranteed to be far from the tabs I was working with. I then find myself hunting around for the tabs I was just at, sometimes trying long and RSI-inducing drag-and-drop operations to regroup things. Sure, if I wanted to strictly manage things, I could always have separate tab groups in this tab set, but often my workflow is more organic than that, and I end up in this place, and I should be able to continue working with the software in the way that my mind expects it to work. So maybe this isn't for you, but I'm Always Right.