Pay with house credit

Steps

1. 1 racer The member already has another checkout open 0:10 ▣

   Opening it is what turns the reservation into an order. Two orders, one balance — which is the whole of this walk.

2. 2 racer Open the event 0:12 ▣
3. 3 racer Buy one GA ticket 0:13

   The five-minute hold starts here. The countdown on this page is that hold, and it is why the page is allowed to sit.

4. 4 racer Offstage: load exactly this order's total, and not a cent more 0:19
5. 5 racer Reload: the balance now covers it, so house credit is offered 0:22 ▣

   Same page, same order. The only thing that changed is the balance, which is what decides whether this control is usable.

6. 6 racer Choose house credit 0:23 ▣
7. 7 racer Now the member spends it somewhere else — another tab, another device, a second order — while this page sits on its five-minute hold. 0:24
8. 8 racer Offstage: the other tab pays, from the same balance the open page is counting on 0:26
9. 9 racer Press Pay on a page that was true when it rendered 0:27 ▣

   The control was enabled when this page was drawn. Nothing on it has changed. The balance behind it has.