A post whose source is a direct link to a Reddit image, rather than to the Reddit post containing the image. These are considered bad links because Danbooru cannot automatically resolve the links to the post.
If you see this warning while uploading, it means you should paste the link to the Reddit post on the upload page, not the image itself.
If the reddit post associated with an image has not been deleted, the proper source can be found through the https://www.reddit.com/media?url= page that preview.redd.it URLs automatically redirect to. If a post is instead sourced to redditmedia.com, it cannot be resolved in the same manner.
