In some VPS templates, they are not installed by default.

Disable DHE ciphers. We don't loose any compatibility as we already use TLS 1.2, and ECDH is faster and safer.
Also, it's better so specify the curve.

This is the conf I use here : https://tls.imirhil.fr/https/mstdn.io

If the file package is not installed, we get "Validation failed: File has contents that are not what they are reported to be" when upload media.

Missing -u parameter to specify the mastodon user.

must be added to the Sidekiq invokation in your systemd file

The pull queue will handle link crawling, thread resolving, and OStatus
processing. Such tasks are more likely to hang for a longer time (due to
network requests) so it is more sensible to not make the "in-house" tasks
wait for them.

Closes GH-745.

Make the streaming API also handle websockets (because trying to get the browser EventSource interface to
work flawlessly was a nightmare). WARNING: This commit makes the web UI connect to the streaming API instead
of ActionCable like before. This means that if you are upgrading, you should set that up beforehand.