This bug doesn't affect wikipedia, but other wikis can link to images elsewhere. Bug reported to
WP:RD with the following text:
"On my mediawiki site, an simple external image code like http://example.com/example.jpg works, but
the gallery tag <gallery>http://example.com/example.jpg</gallery> doesn't work. How do I do it? My
problem is that I already have a hundred file on the server but outside the wiki system and I don't
want to upload them one by one to the wiki again.