Draft internal doc: https://docs.google.com/document/d/1XVkYiMjj6NTGvVm76pWiNIWVGEVIhGg7FMUUiF0sS3I/edit?ts=5baa7202 

This API has been slated for prioritization at the next triage meeting. Will post update here. 

Component Blink>ServiceWorker Pri-0/1 is a bit noisy. Moving this to Pri-2 (esp as there is no target milestone set).

Splitting off Scheduled Notifications into a separate issue 891339

(I don't know what component to use here; used Blink>ServiceWorker since it involves waking up the SW, but I'm not expecting the SW team to pick this up.)

c#3 might have read wrong, I didn't mean to say that "this bug is noise" but that the list [Component=Blink>ServiceWorker Pri=0,1] is full and I'm trying to manage it.

How is that related to periodicSync? https://developer.mozilla.org/en-US/docs/Web/API/ServiceWorkerRegistration/periodicSync

periodicSync comes from an unfinished part of the BackgroundSync proposal: https://github.com/WICG/BackgroundSync/blob/master/explainer.md

It's the same thing. You can look at this issue as "dust off the parts of that proposal that make sense".