diff --git a/mode/gfm/gfm.js b/mode/gfm/gfm.js
index 2f94bb6dd040b7cc382d0f75bc78eeccdff6e56d..08d3820a4a647f32568f65f6e0fc331bef67f04a 100644
--- a/mode/gfm/gfm.js
+++ b/mode/gfm/gfm.js
@@ -11,7 +11,7 @@
 })(function(CodeMirror) {
 "use strict";
 
-var urlRE = /^((?:coap|doi|javascript|aaa|aaas|about|acap|cap|cid|crid|data|dav|dict|dns|file|ftp|geo|go|gopher|h323|http|https|iax|icap|im|imap|info|ipp|iris|iris\.beep|iris\.xpc|iris\.xpcs|iris\.lwz|ldap|mailto|mid|msrp|msrps|mtqp|mupdate|news|nfs|ni|nih|nntp|opaquelocktoken|pop|pres|rtsp|service|session|shttp|sieve|sip|sips|sms|snmp|soap\.beep|soap\.beeps|tag|tel|telnet|tftp|thismessage|tn3270|tip|tv|urn|vemmi|ws|wss|xcon|xcon-userid|xmlrpc\.beep|xmlrpc\.beeps|xmpp|z39\.50r|z39\.50s|adiumxtra|afp|afs|aim|apt|attachment|aw|beshare|bitcoin|bolo|callto|chrome|chrome-extension|com-eventbrite-attendee|content|cvs|dlna-playsingle|dlna-playcontainer|dtn|dvb|ed2k|facetime|feed|finger|fish|gg|git|gizmoproject|gtalk|hcp|icon|ipn|irc|irc6|ircs|itms|jar|jms|keyparc|lastfm|ldaps|magnet|maps|market|message|mms|ms-help|msnim|mumble|mvn|notes|oid|palm|paparazzi|platform|proxy|psyc|query|res|resource|rmi|rsync|rtmp|secondlife|sftp|sgn|skype|smb|soldat|spotify|ssh|steam|svn|teamspeak|things|udp|unreal|ut2004|ventrilo|view-source|webcal|wtai|wyciwyg|xfire|xri|ymsgr:(?:\/{1,3}|[a-z0-9%])|www\d{0,3}[.]|[a-z0-9.\-]+[.][a-z]{2,4}\/)(?:[^\s()<>]|\([^\s()<>]*\))+(?:\([^\s()<>]*\)|[^\s`*!()\[\]{};:'".,<>?«»“”‘’]))/i
+var urlRE = /^((?:(?:aaas?|about|acap|adiumxtra|af[ps]|aim|apt|attachment|aw|beshare|bitcoin|bolo|callto|cap|chrome(?:-extension)?|cid|coap|com-eventbrite-attendee|content|crid|cvs|data|dav|dict|dlna-(?:playcontainer|playsingle)|dns|doi|dtn|dvb|ed2k|facetime|feed|file|finger|fish|ftp|geo|gg|git|gizmoproject|go|gopher|gtalk|h323|hcp|https?|iax|icap|icon|im|imap|info|ipn|ipp|irc[6s]?|iris(?:\.beep|\.lwz|\.xpc|\.xpcs)?|itms|jar|javascript|jms|keyparc|lastfm|ldaps?|magnet|mailto|maps|market|message|mid|mms|ms-help|msnim|msrps?|mtqp|mumble|mupdate|mvn|news|nfs|nih?|nntp|notes|oid|opaquelocktoken|palm|paparazzi|platform|pop|pres|proxy|psyc|query|res(?:ource)?|rmi|rsync|rtmp|rtsp|secondlife|service|session|sftp|sgn|shttp|sieve|sips?|skype|sm[bs]|snmp|soap\.beeps?|soldat|spotify|ssh|steam|svn|tag|teamspeak|tel(?:net)?|tftp|things|thismessage|tip|tn3270|tv|udp|unreal|urn|ut2004|vemmi|ventrilo|view-source|webcal|wss?|wtai|wyciwyg|xcon(?:-userid)?|xfire|xmlrpc\.beeps?|xmpp|xri|ymsgr|z39\.50[rs]?):(?:\/{1,3}|[a-z0-9%])|www\d{0,3}[.]|[a-z0-9.\-]+[.][a-z]{2,4}\/)(?:[^\s()<>]|\([^\s()<>]*\))+(?:\([^\s()<>]*\)|[^\s`*!()\[\]{};:'".,<>?«»“”‘’]))/i
 
 CodeMirror.defineMode("gfm", function(config, modeConfig) {
   var codeDepth = 0;
@@ -95,7 +95,8 @@ CodeMirror.defineMode("gfm", function(config, modeConfig) {
         }
       }
       if (stream.match(urlRE) &&
-         stream.string.slice(stream.start - 2, stream.start) != "](") {
+          stream.string.slice(stream.start - 2, stream.start) != "](" &&
+          (stream.start == 0 || /\W/.test(stream.string.charAt(stream.start - 1)))) {
         // URLs
         // Taken from http://daringfireball.net/2010/07/improved_regex_for_matching_urls
         // And then (issue #1160) simplified to make it not crash the Chrome Regexp engine