MP Customizer Backups
Feel free to play with your Theme Mods under « Appearance » > « Customizer » without worrying about losing your settings! When you are happy with your settings, just click the « Create Backup » button and you’ll always be able to revert to those exact settings in the future. You can even download the backups to make sure you save multiple copies in a safe place.
Or, if you want to develop your customizer locally and then automatically set up those options to match on your live site, simply download a Customizer Backup and Upload it to your live site. You could even send your Customizer settings to your friends or customers.
For Theme/Plugin Developers: This is also a way to create a « Theme within a Theme » – by allowing a single theme to have many different pre-set styles. For example, you could use an activation hook in a plugin to use a backup (in JSON format) and make plugins re-style a Theme. If your plugin does change the Customizer styles, you could also trigger an auto backup of the user’s current settings so that you don’t permanently erase any of the user’s settings.