Last May I had the chance to go to London to speak about developing HTML5 games with Phaser. The conference was WebProgressions, and it was a nice experience!
Some talks I recommend you to watch are Ruth John's Web Audio and Web MIDI (she shows some cool demos!), Progressive WebApps at The Guardian1 by Alex Sanders, and also Sole's Moving to HTTPS with Let's Encrypt.
So here's the video of my talk. I'm sorry there is a some background noise, specially at the beginning. The slides are here, as well as the online demos showing off what is covered in the talk.
Pro tip: Whenever you see a front-end talk delivered by an engineer working for a British newspaper, go watch it. ↩