https://github.com/bleachbit/bleachbit/commit/2614948630d286847ecc843e0622d017c26e2563
Modified to apply as a backport

From 2614948630d286847ecc843e0622d017c26e2563 Mon Sep 17 00:00:00 2001
From: Andrew Ziem <ahz001@gmail.com>
Date: Sun, 1 Feb 2026 15:33:26 -0700
Subject: [PATCH] Fix two GTK deprecation warnings

The zebra striping was not working anyway (tested on Linux and Windows)
--- a/bleachbit/GUI.py
+++ b/bleachbit/GUI.py
@@ -258,7 +258,7 @@ def quit(self, _action=None, _param=None, init_configuration=False):
 
     def get_system_information_dialog(self):
         """Show system information dialog"""
-        dialog = Gtk.Dialog(_("System information"), self._window)
+        dialog = Gtk.Dialog(title=_("System information"), transient_for=self._window)
         dialog.set_default_size(600, 400)
         txtbuffer = Gtk.TextBuffer()
         from bleachbit import SystemInformation