When you install several Firefox versions in Windows (e.g. the stable one, Beta, and ESR), all instances will try to share a common browser profile. This often leads to issues, because changes between versions may break profile compatibility. This changes with Firefox 67.
The popular Firefox browser is available in many different editions. Every edition has its own release channel and has different features, stability, target audience and OS and add-on compatibility. While it is possible to install different Firefox versions in one OS, they all try to use the default browser profile, as a result of which they can't run simultaneously. This lead to crashes, profile corruption and inconveniences.
In this article, we will see which versions of Firefox are available and how to run them simultaneously.