Why does CiviDiscount remove the url parameters after a discount code is applied?
Form submissions will always remove the parameters because they are now in $_POST and for example keeping &quot;reset=1&quot; would mean the form would reset and wouldn't get processed fully. So not just cividiscount. Some forms redirect to a different url and might add some parameters but that's specific to the form.
lcMessages is a bit special and yes maybe it needs some extra handling.