The first thing I wanted to do when I saw this icon added to my browser toolbar was removing it. The first thing I found was that Mozilla's devs have basically said *(^%* you to the user once again and forced a feature that's not strictly necessary.
I used to love this web browser. I spent years happily surfing the web with it and recommending it to all my friends and family.
For the last several years I've found too many issues with it's direction and UI design to even begin my laundry list.
The biggest thing is probably the tab-key behavior in the search bar. That was completely workflow breaking and the aggressive push to force the change by devs was heartbreaking.
I used to love this browser.
Now I hate it. Thanks Mozilla. Sincerely, a frustrated (l)user since version 1.5