Try setting the port to 80
Are you connecting by domain name or by IP address?
So a quick search resulted in this issue from the Yattee repo:
And the highlighted answer states:
Invidious HTTPS Instance needs to be configured with this settings:
external_port: 443 domain: whatever.it.is
Without it, the Invidious frontend will show thumbnails fine but will produce wrong links in the external API used by Yattee.
I just spun up an Invidious instance a week or two ago and I have the same issue using the Yattee app on iOS. If I find an answer I’ll post the solution.
Have you checked the Docker logs for your piped container(s)
https://docs.docker.com/engine/reference/commandline/logs/
Running ‘docker ps’ will show you your running containers which you can then use those names to retrieve the logs.