Android WebView does sandbox the browser and renderer processes since Oreo - https://android-developers.googleblog.com/2017/06/whats-new-in-webview-security.htm

Android WebView does sandbox the browser and renderer processes since Oreo - https://android-developers.googleblog.com/2017/06/whats-new-in-webview-security.html?m=1 https://android-developers.googleblog.com/2017/06/whats-new-... There is no reason Mozilla could not do that with GeckoView.