diff --git a/inc/class-statifyblacklist-admin.php b/inc/class-statifyblacklist-admin.php
index 319a462..a148228 100644
--- a/inc/class-statifyblacklist-admin.php
+++ b/inc/class-statifyblacklist-admin.php
@@ -9,8 +9,10 @@
  * @since     1.0.0
  */
 
-// Quit.
-defined( 'ABSPATH' ) || exit;
+// Quit if accessed directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	exit;
+}
 
 /**
  * Statify Blacklist admin configuration.
diff --git a/inc/class-statifyblacklist-system.php b/inc/class-statifyblacklist-system.php
index 8d65df5..c136d29 100644
--- a/inc/class-statifyblacklist-system.php
+++ b/inc/class-statifyblacklist-system.php
@@ -9,8 +9,10 @@
  * @since     1.0.0
  */
 
-// Quit.
-defined( 'ABSPATH' ) || exit;
+// Quit if accessed directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	exit;
+}
 
 /**
  * Statify Blacklist system configuration.
@@ -25,6 +27,7 @@ class StatifyBlacklist_System extends StatifyBlacklist {
 	 * @since 1.0.0
 	 *
 	 * @param bool $network_wide Whether the plugin was activated network-wide or not.
+	 * @return void
 	 */
 	public static function install( $network_wide = false ) {
 		// Create tables for each site in a network.
@@ -59,6 +62,7 @@ class StatifyBlacklist_System extends StatifyBlacklist {
 	 * @since 1.4.3
 	 *
 	 * @param integer $site_id Site ID.
+	 * @return void
 	 */
 	public static function install_site( $site_id ) {
 		switch_to_blog( (int) $site_id );
@@ -74,6 +78,8 @@ class StatifyBlacklist_System extends StatifyBlacklist {
 	 * Plugin uninstall handler.
 	 *
 	 * @since 1.0.0
+	 *
+	 * @return void
 	 */
 	public static function uninstall() {
 		if ( is_multisite() ) {
@@ -109,6 +115,7 @@ class StatifyBlacklist_System extends StatifyBlacklist {
 	 * @since 1.4.3
 	 *
 	 * @param integer $site_id Site ID.
+	 * @return void
 	 */
 	public static function uninstall_site( $site_id ) {
 		$old = get_current_blog_id();
@@ -121,6 +128,8 @@ class StatifyBlacklist_System extends StatifyBlacklist {
 	 * Upgrade plugin options.
 	 *
 	 * @since 1.2.0
+	 *
+	 * @return void
 	 */
 	public static function upgrade() {
 		self::update_options();
diff --git a/inc/class-statifyblacklist.php b/inc/class-statifyblacklist.php
index d630e25..faf8df3 100644
--- a/inc/class-statifyblacklist.php
+++ b/inc/class-statifyblacklist.php
@@ -8,8 +8,10 @@
  * @since   1.0.0
  */
 
-// Quit.
-defined( 'ABSPATH' ) || exit;
+// Quit if accessed directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	exit;
+}
 
 /**
  * Statify Blacklist.
@@ -42,30 +44,12 @@ class StatifyBlacklist {
 	 */
 	public static $multisite;
 
-	/**
-	 * Class self initialize.
-	 *
-	 * @since 1.0.0
-	 * @deprecated 1.4.2 Replaced by init().
-	 */
-	public static function instance() {
-		self::init();
-	}
-
-	/**
-	 * Class constructor.
-	 *
-	 * @since 1.0.0
-	 * @deprecated 1.4.2 Replaced by init().
-	 */
-	public function __construct() {
-		self::init();
-	}
-
 	/**
 	 * Plugin initialization.
 	 *
 	 * @since 1.4.2
+	 *
+	 * @return void
 	 */
 	public static function init() {
 		// Skip on autosave or AJAX.
@@ -103,6 +87,7 @@ class StatifyBlacklist {
 	 * @since 1.2.1 update_options($options = null) Parameter with default value introduced.
 	 *
 	 * @param array $options Optional. New options to save.
+	 * @return void
 	 */
 	public static function update_options( $options = null ) {
 		if ( self::$multisite ) {
diff --git a/statify-blacklist.php b/statify-blacklist.php
index 892a44b..429754a 100644
--- a/statify-blacklist.php
+++ b/statify-blacklist.php
@@ -10,7 +10,7 @@
  * Plugin Name: Statify Blacklist
  * Plugin URI:  https://wordpress.org/plugins/statify-blacklist/
  * Description: Extension for the Statify plugin to add a customizable blacklists.
- * Version:     1.4.4
+ * Version:     1.5.0-alpha
  * Author:      Stefan Kalscheuer (@stklcode)
  * Author URI:  https://www.stklcode.de
  * Text Domain: statify-blacklist
@@ -30,8 +30,10 @@
  * along with Statify Blacklist. If not, see http://www.gnu.org/licenses/gpl-2.0.html.
  */
 
-// Quit.
-defined( 'ABSPATH' ) || exit;
+// Quit if accessed directly.
+if ( ! defined( 'ABSPATH' ) ) {
+	exit;
+}
 
 // Constants.
 define( 'STATIFYBLACKLIST_FILE', __FILE__ );
@@ -95,6 +97,8 @@ function statify_blacklist_compatibility_check() {
 /**
  * Disable plugin if active and incompatible.
  *
+ * @since 1.5.0
+ *
  * @return void
  */
 function statify_blacklist_disable() {
@@ -110,6 +114,8 @@ function statify_blacklist_disable() {
 /**
  * Admin notification for unmet requirements.
  *
+ * @since 1.5.0
+ *
  * @return void
  */
 function statify_blacklist_disabled_notice() {