> tightly-controlled environments (medical, aerospace, ...) This are places where you don't automatically upgrade browsers but keep them at one specific versio

> tightly-controlled environments (medical, aerospace, ...) This are places where you don't automatically upgrade browsers but keep them at one specific version. No rocket/airplane wants to stop working because something changed. It is also places which are good at writing contracts that can ensure such things to work, so these places should not be a concern. It's likely cheap shoddy sites that will be a problem. The ones that think jQuery is too advanced tech.