Session only on private mode

Kirby 2 Questions šŸ¤”
1

i have been wondering. on a 2.5.2. test envoirment site it seems that sessions ( s::get s::set ) only works within ā€œprivate modeā€ across several browsers for me. while another site works fineā€¦

the thing is, there is no error whatsoever, all tasks run like they are supposed to however a session - or session values are not written when i try to dump the sessions contents it returns empty.

without any change i then run a private mode and try it again (my application is some kind of shopping cart) and it works fine.

is there anything i am missing? i have checked my code many times to see if itā€™s related there ā€¦

s::start();
$session = s::get('cart');

// changed it to make it very simple - as digital product i'll never need to increase qty 
if(param('add')){
  $session[param('cat')][param('add')] = 1;
  s::set('cart', $session);
  go(url::last().'#'.param('add'));
}
if(param('del')){
  unset($session[param('cat')][param('del')]);
  if(empty($session[param('cat')])) unset($session[param('cat')]);
  s::set('cart', $session);
  go(url::last());
}

dump(s::get('cart'));

// incognito works fine, normal access doesn't seem to work.

// Result (s::get('cart')) on incognito array(hash)(filenme)
Array
(
    [pmxo3k] => Array
        (
            [18-55-58.jpg] => 1
            [18-56-58.jpg] => 1
        )

    [13nctcc] => Array
        (
            [0001-20-15-46.jpg] => 1
            [0008-20-19-53.jpg] => 1
        )

)

on https seems to work, http doesnā€™t.