Hi @finks , thanks for the feedback.
That gave me the confidence to move on without SSL, for the time being. I’ve commented out the SSL templates and rebuilt the app.
I got another error in the log but not related to SSL anymore:
/var/www/discourse/vendor/bundle/ruby/2.7.0/gems/unicorn-6.0.0/lib/unicorn/configurator.rb:663:in `set_int': too low (< 1): worker_processes=0 (ArgumentError)
In this case I went on simply forcing the value 1 in the app.yml for the nr of worker.
Now Discord is up and running, and accessible over simple http.
Thanks for the pointer
Cheers
Stef