Hide cpseo meta key data in custom fields on post edit page (#76)

Temporary workaround for #69 .

includes/class-common.php

@@ -55,6 +55,8 @@ public function __construct() {
 			$this->filter( 'auto_update_plugin', 'auto_update_plugin', 10, 2 );
 		}
 
+		$this->filter( 'is_protected_meta', 'hide_cpseo_meta', 10, 2 );
+
 		new Admin_Bar_Menu;
 	}
 
@@ -201,6 +203,19 @@ private function get_stopwords() {
 
 		return array_unique( array_merge( $stopwords, $custom ) );
 	}
+
+
+	/**
+	 * Hide cpseo meta keys
+	 *
+	 * @param bool   $protected Whether the key is considered protected.
+	 * @param string $meta_key  Meta key.
+	 *
+	 * @return bool
+	 */
+	public function hide_cpseo_meta( $protected, $meta_key ) {
+		return Str::starts_with( 'cpseo_', $meta_key ) ? true : $protected;
+	}
 
 	/**
 	 * Filters the permalink for a post of a custom post type.