Since around November last year I have received multiple messages from customers saying that they cannot proceed with checkout as the page goes blank. Customers try on multiple devices and browsers, and the issue persists. Have asked customers to send a screenshot, and the screenshot is just of a white, blank webpage.
Have contacted Shopify and since they cannot replicate the issue, they say nothing can be done.
It’s very worrying, as I wonder how many customers are actually facing this issue who are not contacting me… probably lots.
Anyone else have this issue and any potential solutions? All I can think of is a server capacity issue with Shopify.
Definitely not a server capacity thing - Shopify can handle a massive amount of simultaneous checkouts per merchant and is handling something like 2.2 million merchants. No offence but your store is a tiny drop in the bucket compared to all that 
Even so, when a big store does a flash sale and they are doing thousands of checkouts per second then all that happens is a notification appears saying that you’re in line to check out and to just wait a bit.
If it isn’t possible to replicate it, if even you can’t replicate it, then it’s hard to point at anything besides the customers’ devices. Imagine if it’s fine for you and not fine for a customer, if you hand them your device and their problem doesn’t appear again then it isn’t a Shopify problem. I know that’s not super helpful but at least that’s some extra context about the Shopify side of things.