One of my side projects is Beta Testing the upcoming versions of Mozilla Firefox Browser and Thunderbird Email Client. Mozilla releases Beta builds of both Firefox and Thunderbird starting about six-weeks prior to the scheduled release of the new version. As a Beta Tester I get sneak-peak of new features and functionality that will be included in the upcoming version. This gives me an opportunity to share with my followers via my Firefox and Thunderbird blogs these new features and functionality (as well as ways to workaround these).
For the most part these Beta builds are stable and error free, however there are occasions where an add-on (small program installed within Firefox or Thunderbird to add new or improved functionality) can conflict. These conflicts range from the add-on simply not working to causing Firefox or Thunderbird to stop working. In the event of a conflict I will usually check the user forums to see if this issue has already been reported. If it has not, I will contact the developer of the add-on and let them know of the situation and the circumstances which lead to the conflict. This allows the developer time to get the conflict resolved before Mozilla pushes the new version of Firefox or Thunderbird out to all the users.
Beta builds of both Firefox and Thunderbird are available to the public. Anyone is welcome to try the Beta builds. However, understand that is not a finished product and shouldn't be used in a production environment. In my case, the Beta version of Firefox is my secondary browser and I use Google Chrome as my primary browser.