diff --git a/plugins/captcha/recaptcha_invisible/recaptcha_invisible.php b/plugins/captcha/recaptcha_invisible/recaptcha_invisible.php
index ab21af21100e1..534bd615f38b7 100644
--- a/plugins/captcha/recaptcha_invisible/recaptcha_invisible.php
+++ b/plugins/captcha/recaptcha_invisible/recaptcha_invisible.php
@@ -63,7 +63,6 @@ public function onInit($id = 'dynamic_recaptcha_invisible_1')
 			throw new \RuntimeException(JText::_('PLG_RECAPTCHA_INVISIBLE_ERROR_NO_PUBLIC_KEY'));
 		}
 
-
 		// Load callback first for browser compatibility
 		\JHtml::_(
 			'script',
@@ -83,6 +82,8 @@ public function onInit($id = 'dynamic_recaptcha_invisible_1')
 			array(),
 			array('async' => 'async', 'defer' => 'defer')
 		);
+
+		return true;
 	}
 
 	/**
@@ -119,7 +120,7 @@ public function onDisplay($name = null, $id = 'dynamic_recaptcha_invisible_1', $
 	 *
 	 * @param   string  $code  Answer provided by user. Not needed for the Recaptcha implementation
 	 *
-	 * @return  True if the answer is correct, false otherwise
+	 * @return  boolean  True if the answer is correct, false otherwise
 	 *
 	 * @since   3.9.0
 	 * @throws  \RuntimeException
@@ -177,7 +178,7 @@ public function onSetupField(\Joomla\CMS\Form\Field\CaptchaField $field, \Simple
 	 * @param   string  $remoteip    The remote IP of the visitor.
 	 * @param   string  $response    The response received from Google.
 	 *
-	 * @return bool True if response is good | False if response is bad.
+	 * @return  boolean  True if response is good | False if response is bad.
 	 *
 	 * @since   3.9.0
 	 * @throws  \RuntimeException
diff --git a/plugins/captcha/recaptcha_invisible/recaptcha_invisible.xml b/plugins/captcha/recaptcha_invisible/recaptcha_invisible.xml
index d9f9a92d9f292..f0a1275faa8f9 100644
--- a/plugins/captcha/recaptcha_invisible/recaptcha_invisible.xml
+++ b/plugins/captcha/recaptcha_invisible/recaptcha_invisible.xml
@@ -59,6 +59,7 @@
 					description="PLG_RECAPTCHA_INVISIBLE_TABINDEX_DESC"
 					default="0"
 					min="0"
+					filter="integer"
 				/>
 
 				<field