Allow the browser to cache files (general performance)

Hi,

We've been running dashboards via CDE for a while now and notice that for each url that is loaded in the dashboard there appears to be a ?v={random_number} in the console log. We're worried that if this is truly random that the browser will be attempting to get a clean version each time and not using it's cache.

Can someone please tell us what that 'v' maps too?

Many thanks,

Adam