I stumbled across the following use of
srcset
and
sizes
in an email for the first time.

<img src="image.gif" class="hero-image" width="580" style="border:0; max-width:100%;" srcset="image.gif 580w, large-image.gif?width=1160 1160w" sizes="(max-width: 580px) 100vw, 580px">

Is anyone else is using this in email?

Where is it supported?