diff --git a/packages/rocketchat-ui/getAvatarUrlFromUsername.coffee b/packages/rocketchat-ui/getAvatarUrlFromUsername.coffee
deleted file mode 100644
index 90761f6b720d..000000000000
--- a/packages/rocketchat-ui/getAvatarUrlFromUsername.coffee
+++ /dev/null
@@ -1,19 +0,0 @@
-@getAvatarUrlFromUsername = (username) ->
-	key = "avatar_random_#{username}"
-	random = Session?.keys[key] or 0
-
-	if not username?
-		return
-
-	cdnPrefix = (RocketChat.settings.get('CDN_PREFIX') or '').trim().replace(/\/$/, '')
-	pathPrefix = (__meteor_runtime_config__.ROOT_URL_PATH_PREFIX or '').trim().replace(/\/$/, '')
-
-	if cdnPrefix
-		path = cdnPrefix + pathPrefix
-	else if Meteor.isCordova
-		# Meteor.absoluteUrl alread has path prefix
-		path = Meteor.absoluteUrl().replace(/\/$/, '')
-	else
-		path = pathPrefix
-
-	return "#{path}/avatar/#{encodeURIComponent(username)}?_dc=#{random}"
diff --git a/packages/rocketchat-ui/getAvatarUrlFromUsername.js b/packages/rocketchat-ui/getAvatarUrlFromUsername.js
new file mode 100644
index 000000000000..d9e17c396539
--- /dev/null
+++ b/packages/rocketchat-ui/getAvatarUrlFromUsername.js
@@ -0,0 +1,17 @@
+// TODO: remove global
+this.getAvatarUrlFromUsername = function(username) {
+	const key = `avatar_random_${ username }`;
+	const random = typeof Session !== 'undefined' ? Session.keys[key] : 0;
+	if (username == null) {
+		return;
+	}
+	const cdnPrefix = (RocketChat.settings.get('CDN_PREFIX') || '').trim().replace(/\/$/, '');
+	const pathPrefix = (__meteor_runtime_config__.ROOT_URL_PATH_PREFIX || '').trim().replace(/\/$/, '');
+	let path = pathPrefix;
+	if (cdnPrefix) {
+		path = cdnPrefix + pathPrefix;
+	} else if (Meteor.isCordova) {
+		path = Meteor.absoluteUrl().replace(/\/$/, '');
+	}
+	return `${ path }/avatar/${ encodeURIComponent(username) }?_dc=${ random }`;
+};
diff --git a/packages/rocketchat-ui/package.js b/packages/rocketchat-ui/package.js
index f39733703836..62b946419de4 100644
--- a/packages/rocketchat-ui/package.js
+++ b/packages/rocketchat-ui/package.js
@@ -29,7 +29,7 @@ Package.onUse(function(api) {
 
 	api.use('kadira:flow-router', 'client');
 
-	api.addFiles('getAvatarUrlFromUsername.coffee');
+	api.addFiles('getAvatarUrlFromUsername.js');
 
 	// LIB FILES
 	api.addFiles('client/lib/accountBox.coffee', 'client');