This is so weird. I initially thought that it was a damaged area on my LCD screen. But it pops up when I open a new tab. Its not on just one area of my LCD.
its appearing just above the X that closes the tabs Its a bullet shaped black outline with black lines in it. A little bigger than the X.
Its not on every tab. New tabs get it and if I click on a tab it pops up there. WTH? 
No drinks tonight. I swear! 
Anyone else see it and know what it is?
Sorry I don’t see any. I’m using Firefox 34.0.
I’m using the most updated Firefox and I don’t have that symbol either. I’d try a hard restart and see if comes back. Browsers make me nervous when they do unexpected things as well.
Which virgin of Firefox are you using? I’m using 32 and there are no dots.
Maybe an add-on is doing it. Try disabling them one-by-one to see if it goes away.
I have 34 on my laptop. I’ll try turning off the add ons. If that doesn’t work then its time to uninstall Firefox, delete the folder, and reinstall.
I don’t see those little bullets on my tower pc. Just the laptop.
Click on it if you dare, and see what happens.