The language switcher in barber/beauty headers reads
$currentPageUrlArray[2] unguarded after exploding REQUEST_URI on '/'.
On routes with no language prefix (e.g. POST /manage-booking-cancel
rendering the cancelled page inline), the array has only 2 elements,
triggering "Undefined array key 2" warnings and producing malformed
language links like https://studiobeve.no/en//.
Normalize the array with += [2 => '', 3 => ''] right after the explode
so indices 2 and 3 always exist.
Ubuntu
Astral04