yea, sometimes can do it client side too. I have something where users pick images, the client-side code checks image, and then they can pick to upload directly to bucket. It's b2b software so I really doubt someone would try to jump the check but even if they do it's on them, only they can see their own messed up imgs lol, just want to have sane max upload limits so they can't say "this 1gb file is totally an image"