Hi @sherrikalak & @schoen
Update: Fixed on Mac and iOS by providing the full chain - works for both default and alt chain.
A very similar issue on this thread: SSL Shows Not Valid In Safari and some version of Chrome on Mac computers - I've posted further down in that thread that half my team on MacOS/iOS are struggling to load a few endpoints with Let's Encrypt certificates.
@sherrikalak are you able to load the domains below:
Examples we've deployed quickly that work on all Windows and a minority of MacOS/iOS devices:
https://random.iamonthe.cloud
https://certtest.rightflank.app (a successful tls connection expects a no healthy upstream response)
Is there a wider issue with MacOS/iOS that has not been considered with the rollout of the new root certificates? See: Why won’t Safari open that web page? – The Eclectic Light Company