How to get rid of the cookie button on the bottom left corner of the screen?

[susan]

Why is there suddenly an image of a cookie in the bottom left of my screen?

And why won’t it go away? When I click on it, I get a whole bunch of cookie policy options, and when I agree and click “Save”, the stubborn partially eaten cookie image is still there. What purpose does it now serve except to be an annoying distraction (it partially obscures the “Reply” button)?