[oefrha]

You can totally "download" the image in your RAM by right clicking / long pressing -> "copy image" or equivalent in most browsers. It's just not going to be a byte by byte identical file, and may be in a different format, e.g. you get a public.tiff on the clipboard when you copy an image from Chrome or Safari on macOS, even if the source image is an image/svg+xml.

[snvzz]

That's the first thing I tried, "copy image" then, on gimp, file->create->from clipboard.

And it just worked, with no hassle.