> Google, Wikipedia<p>Caching Google makes no sense beyond some static resources. Wikipedia can be made available off-line, just not by using a man-in-the-middle server. This may make sense for a school with limited connectivity to do.<p>> That’s great for modern browsers, but not everyone has the option to be modern. Sometimes they’re constrained by old operating systems to run older browsers, ones with no service-worker support: a lab full of Windows XP machines limited to IE8, for example.<p>You don't have the option to run legacy browsers <i>and</i> expect everything to work.<p>Just don't use a legacy proprietary OS if you want to go on-line with it. Either install a free (as in gratis, but libre makes sense too) operating system, pay for the windows upgrades, or scrap the computers.