https://github.com/atlassian/commonmark-java

Small with minimal dependencies
Extensible (see below)
Fast (10-20 times faster than pegdown, see benchmarks in repo)

Submitted by Elmer van Chastelet on 1 March 2016 at 13:23

I just switched to use flexmark-java (forked from commonmark-java), as recommended in the deprecation note of pegdown.
I decided to drop support for <verbatim> tags and WebDSL-style WikiLinks, e.g. [[thepage(someArg)|text]]. Normal wikilinks like [[issue/WebDSL/862|are still supported]] should still work (seems broken in our pegdown parser).

Also updated the jsoup lib, allowing use of hash-links in our safe wikitext output.