This blog post discusses various tools and resources for testing, debugging, and understanding HTTP/2 connections on the web. It covers browser add-ons like HTTP/2 and SPDY Indicator extensions for Google Chrome and Firefox, online testing tools such as Claire by CloudFlare, command-line tools including is-http2-cli, curl, nghttp, h2c, openssl s_client, and h2i. It also mentions load testing tool h2load, conformance test tool h2spec, HTTP/2 libraries for different programming languages like C, Go, Ruby, and Haskell, and packet snooping using Wireshark. The post concludes with a Chrome Developer View feature that allows users to see which parts of a web page were downloaded using HTTP/2.