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README.md

 # CodeMirror
 [![Build Status](https://travis-ci.org/codemirror/CodeMirror.svg)](https://travis-ci.org/codemirror/CodeMirror)
-[![NPM version](https://img.shields.io/npm/v/codemirror.svg)](https://www.npmjs.org/package/codemirror)  
+[![NPM version](https://img.shields.io/npm/v/codemirror.svg)](https://www.npmjs.org/package/codemirror)
+[![Join the chat at https://gitter.im/codemirror/CodeMirror](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/codemirror/CodeMirror)  
 [Funding status: ![maintainer happiness](https://marijnhaverbeke.nl/fund/status_s.png?again)](https://marijnhaverbeke.nl/fund/)
 
 CodeMirror is a versatile text editor implemented in JavaScript for