KHTML vs. Gecko vs. Trident vs. Presto

 WebKit Active Apple GNU LGPL, BSD-style Safari browser, plus all browsers for iOS;[3] GNOME Web
Blink Active Google GNU LGPL, BSD-style Google Chrome and all other Chromium-based browsers, notably Microsoft Edge, Brave, Vivaldi, Samsung Internet and Opera[4]
Gecko Active Mozilla Mozilla Public Firefox browser and Thunderbird email client
Goanna[b] Active M. C. Straver[6] Mozilla Public Pale Moon, Basilisk and K-Meleon browsers
Flow Active Ekioh[7] Proprietary Flow browser[8]
Trident[c] Maintained Microsoft Proprietary Internet Explorer browser