Switch from freenode to matrix

README.md

@@ -4,7 +4,7 @@
 [![codecov](https://codecov.io/gh/flaskbb/flaskbb/branch/master/graph/badge.svg)](https://codecov.io/gh/flaskbb/flaskbb)
 [![requires](https://requires.io/github/flaskbb/flaskbb/requirements.svg?branch=master)](https://requires.io/github/flaskbb/flaskbb/requirements/?branch=master)
 [![License](https://img.shields.io/badge/license-BSD-blue.svg)](https://flaskbb.org)
-[![flaskbb@freenode](https://img.shields.io/badge/irc.freenode.net-%23flaskbb-blue.svg)](https://webchat.freenode.net/?channels=flaskbb)
+[![#flaskbb:matrix.org](https://img.shields.io/badge/chat-%23flaskbb%3Amatrix.org-blue)](https://matrix.to/#/#flaskbb:matrix.org)
 
 *FlaskBB is a Forum Software written in Python using the micro framework Flask.*