diff --git a/Dockerfile b/Dockerfile
index 27b27f5..74f666c 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM wordpress:5.8
+FROM wordpress:6
 
 COPY ./entrypoint.sh /usr/local/bin/apache2-custom.sh
 RUN chmod 755 /usr/local/bin/apache2-custom.sh
diff --git a/README.md b/README.md
index 78ff8f6..b757b68 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 Set Advanced Custom Fields (ACF) empty field value as `null` instead of `false` to avoid GraphQL error in GatsbyJS.
 
-## WordPress plugins 
+## WordPress plugins
 
 https://wordpress.org/plugins/wp-acf-nullify-gatsby/
 
@@ -16,6 +16,6 @@ If you would like to report an issue then report it at [GitHub issues](https://g
 
 MIT License
 
-© Jabran Rafique – 2020
+© Jabran Rafique – since 2020
 
 [![Analytics](https://ga-beacon.appspot.com/UA-50688851-1/nullify-empty-fields-for-acf)](https://github.com/igrigorik/ga-beacon)
diff --git a/docker-compose.yml b/docker-compose.yml
index 0db3d2c..ed47981 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -1,6 +1,18 @@
 version: "3.2"
 
 services:
+  db:
+    image: mysql
+    restart: always
+    container_name: mysql
+    environment:
+      MYSQL_DATABASE: exampledb
+      MYSQL_USER: exampleuser
+      MYSQL_PASSWORD: examplepass
+      MYSQL_RANDOM_ROOT_PASSWORD: "1"
+    volumes:
+      - db:/var/lib/mysql
+
   wordpress:
     build: .
     restart: always
@@ -18,18 +30,6 @@ services:
       - plugins:/var/www/html/wp-content/plugins
       - ./src:/var/www/html/wp-content/plugins/nullify-empty-fields-for-acf
 
-  db:
-    image: mysql:5.7
-    restart: always
-    container_name: mysql
-    environment:
-      MYSQL_DATABASE: exampledb
-      MYSQL_USER: exampleuser
-      MYSQL_PASSWORD: examplepass
-      MYSQL_RANDOM_ROOT_PASSWORD: "1"
-    volumes:
-      - db:/var/lib/mysql
-
 volumes:
   wordpress:
   plugins:
diff --git a/src/index.php b/src/index.php
index f6a7aa4..3547571 100644
--- a/src/index.php
+++ b/src/index.php
@@ -1,10 +1,11 @@
 <?php
+
 /**
  * Plugin Name: Nullify empty fields for ACF
  * Plugin URI: https://github.com/jabranr/nullify-empty-fields-for-acf
  * Description: Set Advanced Custom Fields (ACF) empty field value as <code>null</code> instead of <code>false</code> to avoid GraphQL error in GatsbyJS.
  * Author: Jabran Rafique <hello@jabran.me>
- * Version: 1.2.2
+ * Version: 1.2.3
  * Author URI: https://jabran.me?utm_source=nullify-empty-fields-for-acf
  * License: MIT License
  *
@@ -22,9 +23,10 @@
 /**
  * Add settings link
  */
-function nullify_empty_fields_for_acf_settings_link( $links ) {
+function nullify_empty_fields_for_acf_settings_link($links)
+{
     $links[] = sprintf('<a href="%s">%s</a>', admin_url('plugins.php?page=nullify-empty-fields-for-acf'), __('Settings'));
-	return $links;
+    return $links;
 }
 
 /**
@@ -37,7 +39,8 @@ function nullify_empty_fields_for_acf_settings_link( $links ) {
  * @link https://www.gatsbyjs.org/packages/gatsby-source-wordpress/#graphql-error---unknown-field-on-acf
  * @return mixed
  */
-function nullify_empty_fields_for_acf_empty($value, $post_id, $field) {
+function nullify_empty_fields_for_acf_empty($value, $post_id, $field)
+{
     if (empty($value)) {
         return null;
     }
@@ -48,7 +51,8 @@ function nullify_empty_fields_for_acf_empty($value, $post_id, $field) {
 /**
  * Uninstall hook callback function
  */
-function nullify_empty_fields_for_acf_uninstall() {
+function nullify_empty_fields_for_acf_uninstall()
+{
     $nullifyTypes = get_option('nullify_empty_fields_for_acf_types');
 
     if (empty($nullifyTypes)) {
@@ -56,7 +60,7 @@ function nullify_empty_fields_for_acf_uninstall() {
     } else {
         $nullifyTypes = explode(',', $nullifyTypes);
 
-        foreach($nullifyTypes as $nullifyType) {
+        foreach ($nullifyTypes as $nullifyType) {
             if ($remove) {
                 remove_filter('acf/format_value/type=' . $nullifyType, 'nullify_empty_fields_for_acf_empty', 100, 3);
             }
@@ -71,7 +75,8 @@ function nullify_empty_fields_for_acf_uninstall() {
  *
  * @param $remove boolean
  */
-function nullify_empty_fields_for_acf_toggle($remove = false) {
+function nullify_empty_fields_for_acf_toggle($remove = false)
+{
     $nullifyTypes = get_option('nullify_empty_fields_for_acf_types');
 
     if (empty($nullifyTypes)) {
@@ -83,7 +88,7 @@ function nullify_empty_fields_for_acf_toggle($remove = false) {
     } else {
         $nullifyTypes = explode(',', $nullifyTypes);
 
-        foreach($nullifyTypes as $nullifyType) {
+        foreach ($nullifyTypes as $nullifyType) {
             if ($remove) {
                 remove_filter('acf/format_value/type=' . trim($nullifyType), 'nullify_empty_fields_for_acf_empty', 100, 3);
             } else {
@@ -92,20 +97,22 @@ function nullify_empty_fields_for_acf_toggle($remove = false) {
         }
     }
 
-    add_filter('plugin_action_links_'. plugin_basename(__FILE__), 'nullify_empty_fields_for_acf_settings_link', 100, 3);
+    add_filter('plugin_action_links_' . plugin_basename(__FILE__), 'nullify_empty_fields_for_acf_settings_link', 100, 3);
 }
 
 /**
  * Deactivate hook callback function
  */
-function nullify_empty_fields_for_acf_deactivate() {
+function nullify_empty_fields_for_acf_deactivate()
+{
     nullify_empty_fields_for_acf_toggle(true);
 }
 
 /**
  * Activate hook callback function
  */
-function nullify_empty_fields_for_acf_activate() {
+function nullify_empty_fields_for_acf_activate()
+{
     if (!nullify_empty_fields_for_acf_is_acf_active()) {
         wp_die(sprintf('This plugin only works with <a href="%s" target="_blank" rel="noopener">Advanced Custom Fields (ACF)</a>. Please install and activate ACF before using this plugin.', 'https://wordpress.org/plugins/advanced-custom-fields/?utm_source=nullify-empty-fields-for-acf'));
     }
@@ -117,6 +124,6 @@ function nullify_empty_fields_for_acf_activate() {
 nullify_empty_fields_for_acf_toggle();
 
 // hooks
-register_activation_hook( __FILE__, 'nullify_empty_fields_for_acf_activate' );
-register_deactivation_hook( __FILE__, 'nullify_empty_fields_for_acf_deactivate' );
-register_uninstall_hook( __FILE__, 'nullify_empty_fields_for_acf_uninstall' );
+register_activation_hook(__FILE__, 'nullify_empty_fields_for_acf_activate');
+register_deactivation_hook(__FILE__, 'nullify_empty_fields_for_acf_deactivate');
+register_uninstall_hook(__FILE__, 'nullify_empty_fields_for_acf_uninstall');
diff --git a/src/readme.txt b/src/readme.txt
index c2dcac6..2af7968 100644
--- a/src/readme.txt
+++ b/src/readme.txt
@@ -3,8 +3,8 @@ Contributors: jabranr
 Donate link: https://paypal.me/jabranr
 Tags: gatsby, graphql, acf, advanced-custom-fields, wordpress
 Requires at least: 5.0
-Tested up to: 5.8
-Stable tag: 1.2.2
+Tested up to: 6
+Stable tag: 1.2.3
 Requires PHP: 7.1
 License: MIT License
 License URI: https://opensource.org/licenses/MIT
@@ -27,6 +27,9 @@ Set Advanced Custom Fields (ACF) empty field value as `null` instead of `false`
 
 == Changelog ==
 
+= 1.2.3 =
+* Support for WordPress 6.x
+
 = 1.2.2 =
 * Support for WordPress 5.8