MultiFirefox
MultiFirefox is a utility for macOS that allows developers and power users to run multiple independent instances of Firefox simultaneously with separate profiles, caches and configurations. This is useful for testing websites across different user profiles, authentication states, extensions, or browser configurations without needing to launch multiple virtual machines or browser windows. Web developers, QA testers, and security researchers often use profile isolation tools like this when they need to verify behaviour across distinct browser contexts.
AI Recommendation
1 suggestionWe could not find current information about MultiFirefox online, and there is no indication in the bundle ID or available search results whether a native Apple Silicon build has been developed. If you use this app regularly, contact the developer directly through the bundle ID contact information or the app's settings to ask whether a native Apple Silicon version exists or is planned. This matters because Apple is removing Rosetta 2 in macOS 28 (September 2028) — an Intel-only build of MultiFirefox will stop launching after that date. As an alternative, note that newer versions of Firefox itself run natively on Apple Silicon, and you can achieve similar multi-profile testing by running Firefox with the -ProfileManager flag from the terminal to create and switch between separate profiles, though this is less convenient than a dedicated launcher utility. If MultiFirefox remains actively developed, updating to a native version should be your preference once it becomes available.
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