Hi Everyone! I am having some trouble figuring out how to get rid of these "phantom" windows. They appear after I do a sign-in to my Google or Facebook account and it opens in a new window. The windows stay open in the background, or at least my Macbook shows them as windows as if they are still open. Whenever I click on them they just go to my most recently opened tab on Firefox and never actually allow me to click on them or see the tab. I've tried looking for them in the "open tabs" section on Firefox, and it doesn't show them there either. I added a photo to show that the "phantom" window is separate from my currently open browser on Firefox.

If anyone knows how to get rid of these, I would so appreciate your help! Thanks!!!