Introducing Firefox’s new Site Isolation Security Architecture https://hacks.mozilla.org/2021/05/introducing-firefox-new-site-isolation-security-architecture/ Firefox's Site Isolation feature Fission https://www.ghacks.net/2020/09/20/you-can-try-firefoxs-site-isolation-feature-fission-in-nightly-now/ Change how many processes multi-process Firefox uses https://www.ghacks.net/2016/02/15/change-how-many-processes-multi-process-firefox-uses/