Is it possible to upload a fullsized image from DeviantArt to e6? In order to do so I need to download it but whenever I hit the download button I get a “page doesn’t exist message”. Could it be my operating system (iOS) or web browser (Firefox and Safari)?

This is one of those things that seems like nobody else is encountering. I don't have iOS, but everything's working fine with android.

Deviantarts download button isn't actually direct link to largest image, but link with token which opens up in popup window. What I would do is to make sure to have cookies and javascript enabled and disable stuff which could be breaking redirect to direct image like adblocking, bad connection or VPN.

If you are still getting to direct image page, you can try pasting url to direct url upload field and see if it works. Also if it's deviantart you are having issues, I would be googling problems from others or being in contact with deviantart about it.

I think I must have had something disabled that messed with DA because after uninstalling and reinstalling my web browser it worked. Thanks for the help.