diff --git a/phpBB/config/captcha.yml b/phpBB/config/captcha.yml
index 527dba2257..fa40c89045 100644
--- a/phpBB/config/captcha.yml
+++ b/phpBB/config/captcha.yml
@@ -14,30 +14,30 @@ services:
 
     core.captcha.plugins.gd:
         class: phpbb\captcha\plugins\gd
-        scope: prototype # scope MUST be prototype for this to work! # scope MUST be prototype for this to work!
+        scope: prototype # scope MUST be prototype for this to work!
         tags:
             - { name: captchas.plugins }
 
     core.captcha.plugins.gd_wave:
         class: phpbb\captcha\plugins\gd_wave
-        scope: prototype # scope MUST be prototype for this to work! # scope MUST be prototype for this to work!
+        scope: prototype # scope MUST be prototype for this to work!
         tags:
             - { name: captchas.plugins }
 
     core.captcha.plugins.nogd:
         class: phpbb\captcha\plugins\nogd
-        scope: prototype # scope MUST be prototype for this to work! # scope MUST be prototype for this to work!
+        scope: prototype # scope MUST be prototype for this to work!
         tags:
             - { name: captchas.plugins }
 
     core.captcha.plugins.qa:
         class: phpbb\captcha\plugins\qa
-        scope: prototype # scope MUST be prototype for this to work! # scope MUST be prototype for this to work!
+        scope: prototype # scope MUST be prototype for this to work!
         tags:
             - { name: captchas.plugins }
 
     core.captcha.plugins.recaptcha:
         class: phpbb\captcha\plugins\recaptcha
-        scope: prototype # scope MUST be prototype for this to work! # scope MUST be prototype for this to work!
+        scope: prototype # scope MUST be prototype for this to work!
         tags:
             - { name: captchas.plugins }
diff --git a/phpBB/phpbb/db/migration/data/v310/captcha_plugins.php b/phpBB/phpbb/db/migration/data/v310/captcha_plugins.php
index 5e0a09e75a..e6f15ca407 100644
--- a/phpBB/phpbb/db/migration/data/v310/captcha_plugins.php
+++ b/phpBB/phpbb/db/migration/data/v310/captcha_plugins.php
@@ -24,9 +24,10 @@ class captcha_plugins extends \phpbb\db\migration\migration
 
 	public function update_data()
 	{
+		$captcha_plugin = $this->config['captcha_plugin'];
 		if (strpos($this->config['captcha_plugin'], 'phpbb_captcha_') === 0)
 		{
-			$captcha_plugin = substr(strlen('phpbb_captcha_'), $this->config['captcha_plugin']);
+			$captcha_plugin = substr($this->config['captcha_plugin'], strlen('phpbb_captcha_'));
 		}
 
 		return array(