Sitemap Icon Caching

Is it possible to turn off dynamic Icons somehow? I believe it prevents the Browser from caching the icons properly due to the constantly changing url. Without the ?state= querystring parameter it should be fine…

<img data-icon="message_presence_geo_inactive" 

I just minimized all my svg graphics and reduced the total size by 70%, would be nice if the browser could cache them too, it keeps requesting the icons over and over again on site reload. Same should probably be done with Images in the Sitemap too, to reduce bandwidth and requests at Any ideas guys?