Adding HTTP/3 to CloudFront Distributions

CloudFront recently announced HTTP/3 support. I wanted to add it to the CloudFront distributions at work. I looked at the AWS Terraform Provider docs for setting the HTTP version. It said:

The maximum HTTP version to support on the distribution. Allowed values are http1.1, http2, http2and3 and http3. The default is http2.

I was confused about the difference between http2and3 and http3. I looked at the CloudFront API docs, which said pretty much the same thing as the Terraform docs.

I decided to look at the console to see what the options were:

After seeing this, it became a lot clearer what was going on. The documentation says “The maximum HTTP version”, but this is no longer accurate with the release of HTTP/3 support. http3 means HTTP/3 and HTTP/1.1; http2 means HTTP/2 and HTTP/1.1; and http2and3 means HTTP/3, HTTP/2, and HTTP/1.1.