In August of 2015, Mozilla announced that the legacy XPCOM- and XUL-based extension systems would be deprecated in favor of the WebExtension API. Between that date and November, 2017, both legacy and WebExtension add-ons were supported in some fashion. With the release of Firefox 57 (Quantum) in November, 2017, WebExtensions became the only supported API for extension development. Continue reading “Featured Extensions of Firefox Quantum”