What should I do when I notice posts with images hosted on suspicious non-Imgur domains?

Question

The two main issues with posts containing images hosted on non-http://stack.imgur.com/ domains are:

1. Link rot.

2. Potential spam — in case the hoster replaces the images with advertisements.

There are precedents for both cf. Ban ImageShack images because they are reusing old URLs for advertising & What smart ways to prevent “image rot” can we come up with?. And in most cases, such posts don't contain proper attribution for the images either.

Say I come across such a post. What should I do as a user? Here are some options that come to mind:

1. Edit out the non-Imgur images, upload them to Stack Imgur myself and then replace the old image links with the corresponding Stack Imgur links. In this case, there might be some legal problems in case the image wasn't properly attributed in the first place and I'm not aware of what or whom to attribute.

2. Leave a comment on the post asking the OP to shift it to Stack Imgur themselves and provide proper attribution. In case they fail to do so within a day, then I go ahead and vote to close it and perhaps flag it. But in this case, I'm not sure what to flag it as. Even if I use a custom flag, the moderator might face the same dilemma as me. Moreover, Stack Exchange has repeatedly mentioned that it's not a moderator's duty to handle copyright violations.

So...what would you suggest?

Answer 1

You might have noticed (since it is making edits all over the network) that I wrote a bot which performs this task on old posts where the link has broken (because of not existing anymore, or not available via HTTPS, which is a requirement nowadays). It will add a link to the original URL, either in the form of a "source: example.com" blurb under the post, or an HTML comment (the latter if it was originally using an image hoster service; imgur wasn't available in the early years of Stack Exchange). (The bot also uses some heuristics to detect existing attribution.)

So that's more or less your option 1. I am aware that there might be cases where the author used an image hoster and failed to provide attribution; I've accepted that the bot can't fix these cases, and nevertheless improves the post while preserving the author's intent, even if the intent is slightly wrong.

As for option 2, this seems to have the benefit that the author is notified of the issue. But an edit like this is (AFAIK) substantive enough to trigger an inbox notification, so they'll be notified anyway and can rollback the changes if they disagree.

So, all in all, I'd suggest to go for option 1.