Save the first frame of a GIF as a JPG photo — for when you need one still out of an animation.
A GIF can hold many frames, which is how it animates. JPG holds exactly one image. When you convert, your browser decodes the GIF and draws its first frame onto a canvas, and that frame is saved as a JPG. Everything after the first frame is dropped. That makes this conversion useful for pulling a thumbnail or a cover image out of an animation, or for turning a still GIF into a format that photo apps and upload forms handle more readily.
GIF is limited to 256 colours per frame, while JPG stores full colour, so no colours are lost going this direction. Transparency is a different story: GIF supports simple on-or-off transparency, JPG supports none, so transparent pixels become white. If the GIF is a sticker or logo meant to sit on top of other content, PNG is the better target — switch the output format to PNG.
JPG compression is built for photographs. GIFs are often the opposite — flat colours, hard edges, pixel art, text. On those, JPG can add faint blotches around edges and may even produce a larger file than the original. Choose High quality to minimise this, or switch the output to PNG for graphics. For photo-like GIFs, Recommended is usually fine. Files are named after the original with _conv and a .jpg extension.
Everything runs inside your browser. Because the image never reaches a server, we cannot store it or look at it. That difference matters when the file is company material or a personal photo.