Conversation so far:
What is Vortex and Ed the Happy Clown?
Brown began to weave together some of the earlier unrelated strips into an ongoing surreal black comedy called Ed the Happy Clown. Vortex is a comic book publisher
When did Ed the Happy Clown start?
Brown first serialized it in his comic book Yummy Fur, and the first, incomplete collected edition in 1989
When did Ed the Happy Clown end?
He brought Ed to an abrupt end in Yummy Fur #18 to turn to autobiography.
Did Brown collaborate with anyone on the comics?
In 1989 the first Ed collection appeared, collecting the Ed stories from the first twelve issues of Yummy Fur with an introduction by American Splendor writer Harvey Pekar.
Did Chester Brown work with anyone else?
Brown had grown to lose interest in the Ed story as he gravitated toward the autobiographical approach of Pekar, Joe Matt, and Julie Doucet, and the simpler artwork of Seth.
How many comics were published?
He brought Ed to an abrupt end in Yummy Fur #18 to turn to autobiography.

Question: Are there any other interesting aspects about this article?
Self-contained rewrite: Are there any other interesting aspects about this article besides when Ed the Happy Clown started and ended, whom Brown collaborated with and how many Ed comics were published?