Not sure what happened, but I was no longer able to access https://screencred.app. I'm hosting it on fly.io, and using Cloudflare in front of it. Seemed like the fly.io certificate expired.
The trick seemed to be that I needed to make sure my _acme-challenge
CNAME record is unproxied, but keep the A
and AAAA
records proxied in Cloudflare. I now see that the fly.io certificate has been renewed. So hopefully that's all it is.