is this IAB TCF banner from Firefox or have I been hacked

Can someone please explain what this IAB TCF banner is all about, is it Firefox or ?? It leaves a icon like a painter pallet on the bottom right corner of the screen when closed. It says it collect cookies, has a bunch of boxes to check. I clicked reject all, but it didn't go away. What am I supposed to do with it if it is legit. I'm 80 years old and so so tired. I did a spybot virus scan and nothing turned up. appreciate any help that will ease my weary worried mind.