Provider failures on mobile

[ROpdebee]

https://community.metabrainz.org/t/ropdebees-userscripts-support-thread/551947/121?u=ropdebee

Some things I’ve noticed while on mobile:

1. Deezer wants to redirect somewhere else, so fetching from the desktop page fails. Maybe fall back to the API which can still be used without credentials?

2. Bandcamp pages are also slightly different on mobile. Cover art fetching fails even though images are there. Image Max URL also has no trouble.

I'm not "officially" supporting mobile browsers, but if it's easily fixable, we could fix it. Most mobile browsers I know have a toggle to load the desktop page, so I guess we could imitate something similar by changing the some HTTP headers.