Best practices for installing and updating Thunderbird
By default, automatic updates are enabled in Thunderbird. We recommend you keep this feature so your users can have the latest security patches and features. You can ensure that automatic updates are installed without user interference by using the AppAutoUpdate policy.
Beta builds of Thunderbird allow you to test features before they are released to the regular version of Thunderbird. They are a good way to identify issues with upcoming features and updates before they are released to the rest of your organization.