diff --git a/phpBB/assets/javascript/editor.js b/phpBB/assets/javascript/editor.js
index 5b3725d63f..03f42493a2 100644
--- a/phpBB/assets/javascript/editor.js
+++ b/phpBB/assets/javascript/editor.js
@@ -385,6 +385,22 @@ function getCaretPosition(txtarea) {
 }
 
 (function($) {
+	'use strict';
+
+	/**
+	 * Mentions data returned from ajax requests
+	 * @typedef {Object} MentionsData
+	 * @property {string} name User/group name
+	 * @property {string} id User/group ID
+	 * @property {{img: string, group: string}} avatar Avatar data
+	 * @property {string} rank User rank or empty string for groups
+	 * @property {number} priority Priority of data entry
+	 */
+
+	/**
+	 * Mentions class
+	 * @constructor
+	 */
 	function Mentions() {
 		let $mentionDataContainer = $('[data-mention-url]:first');
 		let mentionURL = $mentionDataContainer.data('mentionUrl');
@@ -396,10 +412,20 @@ function getCaretPosition(txtarea) {
 		let cachedAll = [];
 		let cachedSearchKey = 'name';
 
+		/**
+		 * Get default avatar
+		 * @param {string} type Type of avatar; either group or user on any other value
+		 * @returns {string} Default avatar svg code
+		 */
 		function defaultAvatar(type) {
 			return (type === 'group') ? '<svg class="mention-media-avatar" xmlns="http://www.w3.org/2000/svg" viewbox="0 0 24 24"><path fill-rule="evenodd" d="M16 11c1.66 0 2.99-1.34 2.99-3S17.66 5 16 5c-1.66 0-3 1.34-3 3s1.34 3 3 3zm-8 0c1.66 0 2.99-1.34 2.99-3S9.66 5 8 5C6.34 5 5 6.34 5 8s1.34 3 3 3zm0 2c-2.33 0-7 1.17-7 3.5V19h14v-2.5c0-2.33-4.67-3.5-7-3.5zm8 0c-.29 0-.62.02-.97.05 1.16.84 1.97 1.97 1.97 3.45V19h6v-2.5c0-2.33-4.67-3.5-7-3.5z"/></svg>' : '<svg class="mention-media-avatar" xmlns="http://www.w3.org/2000/svg" viewbox="0 0 24 24"><path fill-rule="evenodd" d="M12,19.2C9.5,19.2 7.29,17.92 6,16C6.03,14 10,12.9 12,12.9C14,12.9 17.97,14 18,16C16.71,17.92 14.5,19.2 12,19.2M12,5A3,3 0 0,1 15,8A3,3 0 0,1 12,11A3,3 0 0,1 9,8A3,3 0 0,1 12,5M12,2A10,10 0 0,0 2,12A10,10 0 0,0 12,22A10,10 0 0,0 22,12C22,6.47 17.5,2 12,2Z"/></svg>';
 		}
 
+		/**
+		 * Get cached keyword for query string
+		 * @param {string} query Query string
+		 * @returns {?string} Cached keyword if one fits query, else empty string if cached keywords exist, null if cached keywords do not exist
+		 */
 		function getCachedKeyword(query) {
 			if (!cachedNames) {
 				return null;
@@ -417,6 +443,13 @@ function getCaretPosition(txtarea) {
 			return '';
 		}
 
+		/**
+		 * Get names matching query
+		 * @param {string} query Query string
+		 * @param {Object.<number, MentionsData>} items List of {@link MentionsData} items
+		 * @param {string} searchKey Key to use for matching items
+		 * @returns {Object.<number, MentionsData>} List of {@link MentionsData} items filtered with query and by searchKey
+		 */
 		function getMatchedNames(query, items, searchKey) {
 			let i;
 			let len;
@@ -430,6 +463,11 @@ function getCaretPosition(txtarea) {
 			return _results;
 		}
 
+		/**
+		 * atwho.js remoteFilter callback filter function
+		 * @param {string} query Query string
+		 * @param {function} callback Callback function for filtered items
+		 */
 		function remoteFilter(query, callback) {
 			/*
 			* Do not make a new request until the previous one for the same query is returned
@@ -448,7 +486,7 @@ function getCaretPosition(txtarea) {
 			/*
 			* Use cached values when we can:
 			* 1) There are some names in the cache relevant for the query
-			*    (cache for the query with the same first characters cointains some data)
+			*    (cache for the query with the same first characters contains some data)
 			* 2) We have enough names to display OR
 			*    all relevant names have been fetched from the server
 			*/
@@ -475,8 +513,8 @@ function getCaretPosition(txtarea) {
 			return $mentionDataContainer.length;
 		};
 
-		this.handle = function(txtarea) {
-			$(txtarea).atwho({
+		this.handle = function(textarea) {
+			$(textarea).atwho({
 				at: "@",
 				acceptSpaceBar: true,
 				displayTpl: function(data) {