Hm, actually we try to keep already existing sortorder for albums to be kept. "webp" is a weird order of course… I don't remember that we set any default…
> If I change that option to manual and apply, the custom option disappears, unless I restore the DB.
Yes, it disappears as soon as you change to anything else. It is only meant as a fallback.
"Manual" of course means ordering via drag&drop sorting and not by any specific db column. (Mention it just in case…)
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You basically need a simple admin type plugin that does this (I have not tested if this works via a functions.php of a theme):
zp_register_filter('admin_sortbyoptions', 'yourcustomorder');
function yourcustomorder($orders, $type) {
// you want to sort the images within real albums
if ($type == 'images') {
$orders['Display name for selector'] = 'dbcolumn'; // technically here combinations that are valid sql are possible as before
}
return $orders;
}