Allow katex to work with $...$ and $$...$$

packages/rocketchat-highlight/highlight.coffee

@@ -42,7 +42,7 @@ class Highlight
 						else
 							result = hljs.highlight lang, code
 
-						token = "$#{Random.id()}$"
+						token = "=&=#{Random.id()}=&="
 
 						message.tokens.push
 							highlight: true

packages/rocketchat-katex/katex.coffee

@@ -9,8 +9,8 @@ class Katex
 		'\\(': { closer: '\\)', displayMode: false },
 
 		# Conflicts with message tokens syntax: $token$
-		#'$$' : { closer: '$$' , displayMode: true  },
-		#'$'  : { closer: '$'  , displayMode: false },
+		'$$' : { closer: '$$' , displayMode: true  },
+		'$'  : { closer: '$'  , displayMode: false },
 	}
 
 	# Searches for the first opening delimiter in the string
@@ -80,7 +80,7 @@ class Katex
 		latex = str.substr match.inner.start, match.inner.length()
 		latex = s.unescapeHTML latex
 
-		return { before: before, latex : latex, after : after } 
+		return { before: before, latex : latex, after : after }
 
 	# Takes a latex math string and the desired display mode and renders it
 	# to HTML using the KaTeX library

packages/rocketchat-markdown/markdown.coffee

@@ -19,7 +19,7 @@ class Markdown
 		else
 			message.tokens ?= []
 			msg = msg.replace /(^|&gt;|[ >_*~])\`([^`\r\n]+)\`([<_*~]|\B|\b|$)/gm, (match, p1, p2, p3, offset, text) ->
-				token = "$#{Random.id()}$"
+				token = "=&=#{Random.id()}=&="
 
 				message.tokens.push
 					token: token

packages/rocketchat-ui-message/message/renderMessageBody.js

@@ -13,10 +13,8 @@ renderMessageBody = function(msg) {
 	message = RocketChat.callbacks.run('renderMessage', msg);
 
 	if (message.tokens && message.tokens.length > 0) {
-		for (var i = 0, len = message.tokens.length; i < len; i++) {
-			let token = message.tokens[i];
-			token.text = token.text.replace(/([^\$])(\$[^\$])/gm, '$1$$$2');
-			message.html = message.html.replace(token.token, token.text);
+		for(let {token, text} of message.tokens){
+			message.html = message.html.replace(token, () => text); // Uses lambda so doesn't need to escape $
 		}
 	}