One W3C standard I’m behind on is Server-Sent Events. It became a recommendation earlier this year and has been supported for years by every major browser except for IE and Opera Mini. It would make me happy to see the status for IE Edge change from “Under Consideration” to “In Development.”
I’d like to see this change because WebSockets has gotten a lot of love, and for good reason, but I feel like it’s used a lot to push updates to a page. If the bidirectional communication isn’t needed, let’s not overcomplicate things and stick with the simpler EventSource.