The URL for the source of a piece of content.
The tumblr.post_url target contains a link to a post. The tumblr.source_url target contains a link to content to which the post refers. You can use it for text, photo, quote, link, chat, audio, and video types and for reblogs. For likes and unlikes it is not populated.
- Filter for posts that refer to another post specified by its url:
tumblr.source_url == "http://example.tumblr.com/path"
Target service: Tumblr
Always exists: No