This was brought up before in topic #16318 but not really discussed, but would it be possible to automatically mass mark every URL from defunct domains on the Artist pages?
Off the top of my head, this would include:
drawr.net
friends.nico
geocities.jp
hp.infoseek.co.jp *1
p.twipple.jp (Twipple photos)
summ.jp
theinverviews.jp
twitgoo.com
twitpic.com *2
yfrog.com
- 1 I think most infoseek domains are inactive?
- 2 Although some image urls are active, Danbooru's uploader can't link them to an artist anymore, so twitpic is practically inactive