Worse still: they’ll force your site into the bizarro world of ersatz IE9 or even IE8 “compatibility” through the auspices of “enterprise mode”. There’s nothing like the unique experience of trying to resolve a problem in your modern app, reported by a user who thinks they’re running IE11, but is actually running a never-was IE8 — because the last known developer of some indecipherable ActiveX-festooned internal budgeting app passed away 12 years ago.