I've noticed recently Facebook has started using URLs which seem to include encoded information.
For example, this URL to Vice: https://www.facebook.com/VICE/posts/pfbid02XdVziPTwhmPU9XzBq...
It's a pretty URL with some kind of hash at the end beginning with "pfbid."
Whereas they used to look like basic sharded URLs: https://www.facebook.com/random.username/posts/1020832750980...
Is this for more targeted tracking on posts and links being shared, a new sharding scheme, a combination of both, or something else entirely?
Appreciate any insights the community can provide.
[0] https://www.engadget.com/firefox-can-now-automatically-remov...
Your VICE link is also here, for example:
https://www.facebook.com/VICE/posts/6037626766270531
Edit: To find the old style url, use /plugins/post.php with the new style url passed as a url encoded param value for "href", like: https://www.facebook.com/plugins/post.php?href=https%3A%2F%2...
Then, there's a timestamp like "10 minutes" ago in the returned page that leads to the old url.
I imagine you could make a browser plugin out of that.
Twitter recently started adding a 't=' param to their share links [0] as well, and I can only guess that it's some kind of similar tracking scheme. From watching browser traffic it appears to be generated when you click the share button, but I might be wrong about that.
[0] https://twitter.com/NanoRaptor/status/1548301612246249474?s=... - the first thing in my feed. Link works fine without any of the query params, of course.
I know symmetric encryption is reasonably cheap these days, but anything times “Facebook edge requests” is a lot, I bet any of the cryptographers on here could find out pretty quickly what’s in that blob.
FBIDs are a globally unique id system that they've been using for almost as long as they've been around, if not actually from the beginning.
When the user clicks one of these links, the browser could open it in a headless tab and wait for the URL to change to a non-facebook URL. The browser then remembers that URL, closes the headless tab, and navigates to the underlying URL with tracking parameters stripped.