IT IS VERY, VERY, V E R Y confusing. When introduced in Chrome, I hated it and found a work-around patch to make that entry in the drop-down menu go away. But then Chrome was changed and that work-around made impossible, and I moved all of my browser usage from Chrome to Firefox
And now, you go and do the same thing? WHY? It reminds me of completing companies that open a new store within the area of a competitor instead of an area where there is none of that kind of store and one is needed -- like how Lowe's puts a store NOT where it's needed, but close to a Home Depot. I call this ME TOO inferiority complex. WHY is Mozilla doing this -- just because Chrome did it? It was stupid and I went with the better product.
Now I'm going to have to find some other browser to use -- unless you give us a setting to TURN OFF that feature (removing it from the drop down menu where we are use to the second choice being open in a new window.
Especially for those of us who can't see 2 tiny screens, side by side, but need to open things in its own, big window to be able to see it. This will just NOT work for me, so PLEASE, give a switch to suppress this stupid feature.