sl_upload($_FILES['quest']['tmp_name'][$this->id], $path.$savefile, null);
sl_upload function is expecting 3 arguments, and you’re passing only 2.
Since it worked fine for you before (although, it must have triggered a Warning, which probably got logged somewhere unless your
error_reporting is very lax), passing
null as the third argument should produce the same outcome as it used to.
It would, however, be a better idea to figure out what that function argument is supposed to be used for, as it’s marked as required (no default value).
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