Comprehensive permutation testing of Web Pages module in both light and dark modes. Verified 6 areas: Pages Management tree, Popover action buttons, Settings Panel (9 accordions), Main Template tab, CSS Codes tab, Website Settings tab. Fixes: (1) Popover dark mode — added CSS for .popover, .popover-body, .popover-body .btn-group in [data-bs-theme=dark]. (2) security.php JS crash — data.module_roles.split() failed on undefined, fixed with (data.module_roles || "").split(). All areas verified zero errors in both modes.