Sometimes, in the course of your research, you open a slew of tabs, and then realize, for one reason or another, that the order of the tabs is less than optimal. Don't forget that in all browsers you can remedy this situation by dragging tabs into an order that more approximately suits your needs.
In this case, I want my ancestry.com tab to move to the second tab position. Just click and hold the tab, then drag the cursor to place you want the tab to be:
Release the button, and voila'!
Your tabs are reordered like magic, and your addled brain has one less hurdle to overcome while doing vast amounts of online genealogy research!