My account has MobileFrontend beta enabled and when browsing on https://en.wikipedia.org/wiki/Main_Page (desktop site), the window.NORLQ section for MobileFrontendSkinHooks::gradeCImageSupport() is being included, which seems unrelated to the Vector skin and Desktop mode as the actual functionality this relates to is only enabled in Mobile context (currently Minerva skin).
It should probably use MobileContext::shouldDisplayMobileView() or a similar conditional.