This release has one significant new feature designed to help designers: style designer mode. When this mode is enabled, template edits and customized style properties will be written out to the file system, similar to development mode output for add-ons. Significantly, this also means that templates can be edited directly within the file system and the changes will be automatically picked up when the relevant page is loaded. Beyond that, designer mode should more easily enable designers to use version control and have multiple people collaborate on a style. Designer mode is enabled on a per-style basis using some CLI commands. You can learn more in the designing a style section of the developer docs.
Beyond that, this release also simplifies the registration form by removing the date of birth field unless it's required and integrates a variety of bug fixes.
Installing the new release
As per the initial developer preview announcement, there are no upgrade options between developer previews. As such, our recommended course of action is a fresh install (in a new directory) or a re-installation (in the existing directory). If you are doing a reinstallation in this manner, you should pay attention to our specific reinstallation guidelines.