The following patch versions were released since Cowboy 2.2:
Cowboy 2.2.2
While fixing the miscount in the previous patch release an issue was introduced where HTTP/2 bodies could be sent out of orders when using iolists. This has been corrected.
Cowboy 2.2.1
Colons are now allowed within path segments in routes provided to cowboy_router:compile/1 as long as they are not the first character of the path segment.
The cowboy_req:delete_resp_header/2 function will no longer crash when no response header was set before calling it.
A miscount of the output HTTP/2 flow control window has been fixed. It prevented sending the response body fully with some clients. The issue only affected response bodies sent as iolists.