Enable ALPN under Debian 10 Buster

How to enable ALPN support in nginx:

echo "deb http://nginx.org/packages/debian `lsb_release -cs` nginx" \
    | sudo tee /etc/apt/sources.list.d/nginx.list

When you choose to install nginx from the official nginx repositories instead of the debian ones, you will get the newest version with ALPN support (Application-Layer Protocol Negotiation).

Just do an apt-get update & apt-get upgrade and you will get version 1.16.0-1~buster which includes it.

Here you can verify if it worked:

https://tools.keycdn.com/http2-test