Description:
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When i save $_SESSION to some local variable then afterwards what ever i put into $_SESSION has no affect on next page load, from the moment when $_SESSION is saved into new variable it seems nothing is written into actual session anymore.

Reproduce code:
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<?php 

session_start(); 

print_r($_SESSION); 
$session = $_SESSION;  // without this line it works ok 
$_SESSION['test'] = 1000; 

?>

Expected result:
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You need to run this code atleast twice so that first time session is set and next time it should be printed out but the thing is that i always get empty array.