// Improve installation design (addons iframes + progress percent + remove back button)

install-dev/classes/controllerHttp.php

@@ -64,6 +64,11 @@ abstract class InstallControllerHttp
 	 */
 	public $next_button = true;
 
+	/**
+	 * @var bool If false, disable previous button access
+	 */
+	public $previous_button = true;
+
 	/**
 	 * @var InstallAbstractModel
 	 */