diff --git a/CHANGELOG.md b/CHANGELOG.md
index 59e02653..32fca586 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,20 @@
+## **6.2.4**
+- [Fix] `parse`: ignore `__proto__` keys (#428)
+- [Fix] `utils.merge`: avoid a crash with a null target and an array source
+- [Fix] `utils.merge`: avoid a crash with a null target and a truthy non-array source
+- [Fix] `utils`: `merge`: fix crash when `source` is a truthy primitive & no options are provided
+- [Fix] when `parseArrays` is false, properly handle keys ending in `[]`
+- [Robustness] `stringify`: avoid relying on a global `undefined` (#427)
+- [Refactor] use cached `Array.isArray`
+- [Docs] Clarify the need for "arrayLimit" option
+- [meta] fix README.md (#399)
+- [meta] Clean up license text so it’s properly detected as BSD-3-Clause
+- [meta] add FUNDING.yml
+- [actions] backport actions from main
+- [Tests] use `safer-buffer` instead of `Buffer` constructor
+- [Tests] remove nonexistent tape option
+- [Dev Deps] backport from main
+
 ## **6.2.3**
 - [Fix] follow `allowPrototypes` option during merge (#201, #200)
 - [Fix] chmod a-x
diff --git a/component.json b/component.json
index c1715a89..5fed22a4 100644
--- a/component.json
+++ b/component.json
@@ -2,7 +2,7 @@
     "name": "qs",
     "repository": "hapijs/qs",
     "description": "query-string parser / stringifier with nesting support",
-    "version": "6.2.3",
+    "version": "6.2.4",
     "keywords": ["querystring", "query", "parser"],
     "main": "lib/index.js",
     "scripts": [
diff --git a/dist/qs.js b/dist/qs.js
index bcac0f0c..c9a48916 100644
--- a/dist/qs.js
+++ b/dist/qs.js
@@ -1,4 +1,4 @@
-(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.Qs = f()}})(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
+(function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.Qs = f()}})(function(){var define,module,exports;return (function(){function r(e,n,t){function o(i,f){if(!n[i]){if(!e[i]){var c="function"==typeof require&&require;if(!f&&c)return c(i,!0);if(u)return u(i,!0);var a=new Error("Cannot find module '"+i+"'");throw a.code="MODULE_NOT_FOUND",a}var p=n[i]={exports:{}};e[i][0].call(p.exports,function(r){var n=e[i][1][r];return o(n||r)},p,p.exports,r,e,n,t)}return n[i].exports}for(var u="function"==typeof require&&require,i=0;i<t.length;i++)o(t[i]);return o}return r})()({1:[function(require,module,exports){
 'use strict';
 
 var Stringify = require('./stringify');
@@ -62,23 +62,25 @@ var parseObject = function parseObject(chain, val, options) {
     var root = chain.shift();
 
     var obj;
-    if (root === '[]') {
+    if (root === '[]' && options.parseArrays) {
         obj = [];
         obj = obj.concat(parseObject(chain, val, options));
     } else {
         obj = options.plainObjects ? Object.create(null) : {};
         var cleanRoot = root.charAt(0) === '[' && root.charAt(root.length - 1) === ']' ? root.slice(1, -1) : root;
         var index = parseInt(cleanRoot, 10);
-        if (
-            !isNaN(index) &&
-            root !== cleanRoot &&
-            String(index) === cleanRoot &&
-            index >= 0 &&
-            (options.parseArrays && index <= options.arrayLimit)
+        if (!options.parseArrays && cleanRoot === '') {
+            obj = { 0: val };
+        } else if (
+            !isNaN(index)
+            && root !== cleanRoot
+            && String(index) === cleanRoot
+            && index >= 0
+            && (options.parseArrays && index <= options.arrayLimit)
         ) {
             obj = [];
             obj[index] = parseObject(chain, val, options);
-        } else {
+        } else if (cleanRoot !== '__proto__') {
             obj[cleanRoot] = parseObject(chain, val, options);
         }
     }
@@ -108,8 +110,7 @@ var parseKeys = function parseKeys(givenKey, val, options) {
 
     var keys = [];
     if (parent) {
-        // If we aren't using plain objects, optionally prefix keys
-        // that would overwrite object prototype properties
+        // If we aren't using plain objects, optionally prefix keys that would overwrite object prototype properties
         if (!options.plainObjects && has.call(Object.prototype, parent)) {
             if (!options.allowPrototypes) {
                 return;
@@ -203,7 +204,18 @@ var defaults = {
     encoder: Utils.encode
 };
 
-var stringify = function stringify(object, prefix, generateArrayPrefix, strictNullHandling, skipNulls, encoder, filter, sort, allowDots) {
+var isArray = Array.isArray;
+var stringify = function stringify(
+    object,
+    prefix,
+    generateArrayPrefix,
+    strictNullHandling,
+    skipNulls,
+    encoder,
+    filter,
+    sort,
+    allowDots
+) {
     var obj = object;
     if (typeof filter === 'function') {
         obj = filter(prefix, obj);
@@ -231,7 +243,7 @@ var stringify = function stringify(object, prefix, generateArrayPrefix, strictNu
     }
 
     var objKeys;
-    if (Array.isArray(filter)) {
+    if (isArray(filter)) {
         objKeys = filter;
     } else {
         var keys = Object.keys(obj);
@@ -245,10 +257,30 @@ var stringify = function stringify(object, prefix, generateArrayPrefix, strictNu
             continue;
         }
 
-        if (Array.isArray(obj)) {
-            values = values.concat(stringify(obj[key], generateArrayPrefix(prefix, key), generateArrayPrefix, strictNullHandling, skipNulls, encoder, filter, sort, allowDots));
+        if (isArray(obj)) {
+            values = values.concat(stringify(
+                obj[key],
+                generateArrayPrefix(prefix, key),
+                generateArrayPrefix,
+                strictNullHandling,
+                skipNulls,
+                encoder,
+                filter,
+                sort,
+                allowDots
+            ));
         } else {
-            values = values.concat(stringify(obj[key], prefix + (allowDots ? '.' + key : '[' + key + ']'), generateArrayPrefix, strictNullHandling, skipNulls, encoder, filter, sort, allowDots));
+            values = values.concat(stringify(
+                obj[key],
+                prefix + (allowDots ? '.' + key : '[' + key + ']'),
+                generateArrayPrefix,
+                strictNullHandling,
+                skipNulls,
+                encoder,
+                filter,
+                sort,
+                allowDots
+            ));
         }
     }
 
@@ -262,21 +294,22 @@ module.exports = function (object, opts) {
     var strictNullHandling = typeof options.strictNullHandling === 'boolean' ? options.strictNullHandling : defaults.strictNullHandling;
     var skipNulls = typeof options.skipNulls === 'boolean' ? options.skipNulls : defaults.skipNulls;
     var encode = typeof options.encode === 'boolean' ? options.encode : defaults.encode;
-    var encoder = encode ? (typeof options.encoder === 'function' ? options.encoder : defaults.encoder) : null;
+    var encoder = encode ? typeof options.encoder === 'function' ? options.encoder : defaults.encoder : null;
     var sort = typeof options.sort === 'function' ? options.sort : null;
     var allowDots = typeof options.allowDots === 'undefined' ? false : options.allowDots;
     var objKeys;
     var filter;
 
-    if (options.encoder !== null && options.encoder !== undefined && typeof options.encoder !== 'function') {
+    if (options.encoder !== null && typeof options.encoder !== 'undefined' && typeof options.encoder !== 'function') {
         throw new TypeError('Encoder has to be a function.');
     }
 
     if (typeof options.filter === 'function') {
         filter = options.filter;
         obj = filter('', obj);
-    } else if (Array.isArray(options.filter)) {
-        objKeys = filter = options.filter;
+    } else if (isArray(options.filter)) {
+        objKeys = options.filter;
+        filter = options.filter;
     }
 
     var keys = [];
@@ -311,7 +344,17 @@ module.exports = function (object, opts) {
             continue;
         }
 
-        keys = keys.concat(stringify(obj[key], key, generateArrayPrefix, strictNullHandling, skipNulls, encoder, filter, sort, allowDots));
+        keys = keys.concat(stringify(
+            obj[key],
+            key,
+            generateArrayPrefix,
+            strictNullHandling,
+            skipNulls,
+            encoder,
+            filter,
+            sort,
+            allowDots
+        ));
     }
 
     return keys.join(delimiter);
@@ -332,7 +375,20 @@ var hexTable = (function () {
 var has = Object.prototype.hasOwnProperty;
 
 exports.arrayToObject = function (source, options) {
-    var obj = options.plainObjects ? Object.create(null) : {};
+    var obj = options && options.plainObjects ? Object.create(null) : {};
+    for (var i = 0; i < source.length; ++i) {
+        if (typeof source[i] !== 'undefined') {
+            obj[i] = source[i];
+        }
+    }
+
+    return obj;
+};
+
+var isArray = Array.isArray;
+
+var arrayToObject = function arrayToObject(source, options) {
+    var obj = options && options.plainObjects ? Object.create(null) : {};
     for (var i = 0; i < source.length; ++i) {
         if (typeof source[i] !== 'undefined') {
             obj[i] = source[i];
@@ -342,16 +398,17 @@ exports.arrayToObject = function (source, options) {
     return obj;
 };
 
-exports.merge = function (target, source, options) {
+exports.merge = function merge(target, source, options) {
+    /* eslint no-param-reassign: 0 */
     if (!source) {
         return target;
     }
 
     if (typeof source !== 'object') {
-        if (Array.isArray(target)) {
+        if (isArray(target)) {
             target.push(source);
-        } else if (typeof target === 'object') {
-            if (options.plainObjects || options.allowPrototypes || !has.call(Object.prototype, source)) {
+        } else if (target && typeof target === 'object') {
+            if ((options && (options.plainObjects || options.allowPrototypes)) || !has.call(Object.prototype, source)) {
                 target[source] = true;
             }
         } else {
@@ -361,20 +418,36 @@ exports.merge = function (target, source, options) {
         return target;
     }
 
-    if (typeof target !== 'object') {
+    if (!target || typeof target !== 'object') {
         return [target].concat(source);
     }
 
     var mergeTarget = target;
-    if (Array.isArray(target) && !Array.isArray(source)) {
-        mergeTarget = exports.arrayToObject(target, options);
+    if (isArray(target) && !isArray(source)) {
+        mergeTarget = arrayToObject(target, options);
+    }
+
+    if (isArray(target) && isArray(source)) {
+        source.forEach(function (item, i) {
+            if (has.call(target, i)) {
+                var targetItem = target[i];
+                if (targetItem && typeof targetItem === 'object' && item && typeof item === 'object') {
+                    target[i] = merge(targetItem, item, options);
+                } else {
+                    target.push(item);
+                }
+            } else {
+                target[i] = item;
+            }
+        });
+        return target;
     }
 
     return Object.keys(source).reduce(function (acc, key) {
         var value = source[key];
 
         if (has.call(acc, key)) {
-            acc[key] = exports.merge(acc[key], value, options);
+            acc[key] = merge(acc[key], value, options);
         } else {
             acc[key] = value;
         }
@@ -404,13 +477,13 @@ exports.encode = function (str) {
         var c = string.charCodeAt(i);
 
         if (
-            c === 0x2D || // -
-            c === 0x2E || // .
-            c === 0x5F || // _
-            c === 0x7E || // ~
-            (c >= 0x30 && c <= 0x39) || // 0-9
-            (c >= 0x41 && c <= 0x5A) || // a-z
-            (c >= 0x61 && c <= 0x7A) // A-Z
+            c === 0x2D // -
+            || c === 0x2E // .
+            || c === 0x5F // _
+            || c === 0x7E // ~
+            || (c >= 0x30 && c <= 0x39) // 0-9
+            || (c >= 0x41 && c <= 0x5A) // a-z
+            || (c >= 0x61 && c <= 0x7A) // A-Z
         ) {
             out += string.charAt(i);
             continue;
@@ -433,7 +506,11 @@ exports.encode = function (str) {
 
         i += 1;
         c = 0x10000 + (((c & 0x3FF) << 10) | (string.charCodeAt(i) & 0x3FF));
-        out += hexTable[0xF0 | (c >> 18)] + hexTable[0x80 | ((c >> 12) & 0x3F)] + hexTable[0x80 | ((c >> 6) & 0x3F)] + hexTable[0x80 | (c & 0x3F)];
+        /* eslint operator-linebreak: [2, "before"] */
+        out += hexTable[0xF0 | (c >> 18)]
+            + hexTable[0x80 | ((c >> 12) & 0x3F)]
+            + hexTable[0x80 | ((c >> 6) & 0x3F)]
+            + hexTable[0x80 | (c & 0x3F)];
     }
 
     return out;
@@ -452,7 +529,7 @@ exports.compact = function (obj, references) {
 
     refs.push(obj);
 
-    if (Array.isArray(obj)) {
+    if (isArray(obj)) {
         var compacted = [];
 
         for (var i = 0; i < obj.length; ++i) {
@@ -488,4 +565,4 @@ exports.isBuffer = function (obj) {
 };
 
 },{}]},{},[1])(1)
-});
\ No newline at end of file
+});
diff --git a/package.json b/package.json
index b248fb9d..b1dcf19e 100644
--- a/package.json
+++ b/package.json
@@ -2,7 +2,7 @@
     "name": "qs",
     "description": "A querystring parser that supports nesting and arrays, with a depth limit",
     "homepage": "https://github.com/ljharb/qs",
-    "version": "6.2.3",
+    "version": "6.2.4",
     "repository": {
         "type": "git",
         "url": "https://github.com/ljharb/qs.git"