As of the 23th of May 2019, 11:35 EVE o’ clock.
Format is simple:
id, timestamp, slug, newline. seperated by spaces.
A “slug” is what you see in the address bar when you’re in a thread/topic.
The italic above is the slug, the fat is the ID.
You can reference threads either by their slug …
… or by their ID directly: https://forums.eveonline.com/t/161418