Hi

Within our app we are doing a ZAFClient request to our server to retrieve some data. This has worked for a couple of years but yesterday it just stopped working (app went blank).

After troubleshooting we could establish the server side was working just fine, requests were coming through. In the JS-console we could see an error on app load and it looked like this:

Req: https://[instance].zendesk.com/proxy/v2/apps/secure/https%3A%2F%2F...
Resp: HTTP 504, Proxy error: Errno::EPROTO

We use Lets Encrypt SSL on that particular server. Given that LE root certs expired 30 Sep 2021, does this have anything to do with this sudden problem? When looking via tcpdump we can see the sslhandshake coming in but then disconnects without request.

I would appreciate feedback on this topic, thanks in advance.