Tested all 24 AJAX endpoints in Web Pages module. Fixed 7 additional failures: (1) get.submenu.php — $siteidget typo, should be $siteid (lines 45,54). (2) get.parentmenu.php — $menuValue used in parent loop instead of correct iterator variable; also fixed over-aggressive replace_all that changed parent-loop $menuValue to $childValue. Added ?? fallbacks for moduleListResult keys. (3) update.websettings.php — 7 $_POST keys without ?? fallback. (4) update.maincss.php — 7 $_POST keys without ?? fallback. (5) update.topbarcss.php — $_POST keys without ?? fallback + Sdba object compared to int (changed to ->is_error()). (6) update.defaultmenu.php — $_POST keys without ?? fallback. All 24 endpoints now return clean responses with zero PHP warnings.