diff --git a/phpBB/adm/style/captcha_recaptcha_acp.html b/phpBB/adm/style/captcha_recaptcha_acp.html
index 67176ebd07..c31cfa7a1b 100644
--- a/phpBB/adm/style/captcha_recaptcha_acp.html
+++ b/phpBB/adm/style/captcha_recaptcha_acp.html
@@ -21,6 +21,20 @@
 	<dd><input id="recaptcha_privkey" name="recaptcha_privkey" value="{RECAPTCHA_PRIVKEY}" size="50" type="text" /></dd>
 </dl>
 
+<dl>
+	<dt>
+		<label>{{ lang('RECAPTCHA_V3_DOMAIN') ~ lang('COLON') }}</label>
+		<br><span>{{ lang('RECAPTCHA_V3_DOMAIN_EXPLAIN') }}</span>
+	</dt>
+	<dd>
+		{% for domain in RECAPTCHA_V2_DOMAINS %}
+		<label>
+			<input class="radio" name="recaptcha_v2_domain" type="radio" value="{{ domain }}"{{ domain == RECAPTCHA_V2_DOMAIN ? ' checked' }}>
+			<span>{{ domain }}</span>
+		</label>
+		{% endfor %}
+	</dd>
+</dl>
 
 </fieldset>
 <fieldset>
diff --git a/phpBB/phpbb/captcha/plugins/recaptcha.php b/phpBB/phpbb/captcha/plugins/recaptcha.php
index b7c0b5f5e2..4292080390 100644
--- a/phpBB/phpbb/captcha/plugins/recaptcha.php
+++ b/phpBB/phpbb/captcha/plugins/recaptcha.php
@@ -15,18 +15,13 @@ namespace phpbb\captcha\plugins;
 
 class recaptcha extends captcha_abstract
 {
-	var $recaptcha_server = 'http://www.google.com/recaptcha/api';
-	var $recaptcha_server_secure = 'https://www.google.com/recaptcha/api'; // class constants :(
-
-	var $response;
+	private $response;
 
 	/**
 	* Constructor
 	*/
 	public function __construct()
 	{
-		global $request;
-		$this->recaptcha_server = $request->is_secure() ? $this->recaptcha_server_secure : $this->recaptcha_server;
 	}
 
 	function init($type)
@@ -94,6 +89,12 @@ class recaptcha extends captcha_abstract
 				}
 			}
 
+			$recaptcha_domain = $request->variable('recaptcha_v2_domain', '', true);
+			if (in_array($recaptcha_domain, recaptcha_v3::$supported_domains))
+			{
+				$config->set('recaptcha_v2_domain', $recaptcha_domain);
+			}
+
 			$phpbb_log->add('admin', $user->data['user_id'], $user->ip, 'LOG_CONFIG_VISUAL');
 			trigger_error($user->lang['CONFIG_UPDATED'] . adm_back_link($module->u_action));
 		}
@@ -110,9 +111,11 @@ class recaptcha extends captcha_abstract
 			}
 
 			$template->assign_vars(array(
-				'CAPTCHA_PREVIEW'	=> $this->get_demo_template($id),
-				'CAPTCHA_NAME'		=> $this->get_service_name(),
-				'U_ACTION'			=> $module->u_action,
+				'CAPTCHA_PREVIEW'		=> $this->get_demo_template($id),
+				'CAPTCHA_NAME'			=> $this->get_service_name(),
+				'RECAPTCHA_V2_DOMAIN'	=> $config['recaptcha_v2_domain'] ?? recaptcha_v3::GOOGLE,
+				'RECAPTCHA_V2_DOMAINS'	=> recaptcha_v3::$supported_domains,
+				'U_ACTION'				=> $module->u_action,
 			));
 
 		}
@@ -140,9 +143,10 @@ class recaptcha extends captcha_abstract
 		{
 			$contact_link = phpbb_get_board_contact_link($config, $phpbb_root_path, $phpEx);
 			$explain = $user->lang(($this->type != CONFIRM_POST) ? 'CONFIRM_EXPLAIN' : 'POST_CONFIRM_EXPLAIN', '<a href="' . $contact_link . '">', '</a>');
+			$domain = $config['recaptcha_v2_domain'] ?? recaptcha_v3::GOOGLE;
 
 			$template->assign_vars(array(
-				'RECAPTCHA_SERVER'			=> $this->recaptcha_server,
+				'RECAPTCHA_SERVER'			=> sprintf('//%1$s/recaptcha/api', $domain),
 				'RECAPTCHA_PUBKEY'			=> isset($config['recaptcha_pubkey']) ? $config['recaptcha_pubkey'] : '',
 				'S_RECAPTCHA_AVAILABLE'		=> self::is_available(),
 				'S_CONFIRM_CODE'			=> true,
diff --git a/phpBB/phpbb/captcha/plugins/recaptcha_v3.php b/phpBB/phpbb/captcha/plugins/recaptcha_v3.php
index cc81da7b9d..6afa18691f 100644
--- a/phpBB/phpbb/captcha/plugins/recaptcha_v3.php
+++ b/phpBB/phpbb/captcha/plugins/recaptcha_v3.php
@@ -30,6 +30,14 @@ class recaptcha_v3 extends captcha_abstract
 	 */
 	const GOOGLE		= 'google.com';
 	const RECAPTCHA		= 'recaptcha.net';
+	const RECAPTCHA_CN	= 'recaptcha.google.cn';
+
+	/** @var string[] List of supported domains */
+	static public $supported_domains = [
+		self::GOOGLE,
+		self::RECAPTCHA,
+		self::RECAPTCHA_CN
+	];
 
 	/** @var array CAPTCHA types mapped to their action */
 	static protected $actions = [
@@ -180,9 +188,14 @@ class recaptcha_v3 extends captcha_abstract
 				trigger_error($language->lang('EMPTY_RECAPTCHA_V3_REQUEST_METHOD') . adm_back_link($module->u_action), E_USER_WARNING);
 			}
 
+			$recaptcha_domain = $request->variable('recaptcha_v3_domain', '', true);
+			if (in_array($recaptcha_domain, self::$supported_domains))
+			{
+				$config->set('recaptcha_v3_domain', $recaptcha_domain);
+			}
+
 			$config->set('recaptcha_v3_key', $request->variable('recaptcha_v3_key', '', true));
 			$config->set('recaptcha_v3_secret', $request->variable('recaptcha_v3_secret', '', true));
-			$config->set('recaptcha_v3_domain', $request->variable('recaptcha_v3_domain', '', true));
 			$config->set('recaptcha_v3_method', $recaptcha_v3_method);
 
 			foreach (self::$actions as $action)
@@ -211,7 +224,7 @@ class recaptcha_v3 extends captcha_abstract
 			'RECAPTCHA_V3_SECRET'		=> $config['recaptcha_v3_secret'] ?? '',
 
 			'RECAPTCHA_V3_DOMAIN'		=> $config['recaptcha_v3_domain'] ?? self::GOOGLE,
-			'RECAPTCHA_V3_DOMAINS'		=> [self::GOOGLE, self::RECAPTCHA],
+			'RECAPTCHA_V3_DOMAINS'		=> self::$supported_domains,
 
 			'RECAPTCHA_V3_METHOD'		=> $config['recaptcha_v3_method'] ?? '',
 			'RECAPTCHA_V3_METHODS'		=> [