Preview theme in WordPress

Preview theme in WordPress In the latest version of WordPress, it gives you the opportunity to view a preview of what your site would look like using a different theme. You basically just click on the theme, it takes over the screen and you have a chance to activate or close it (and return to the previous screen, which is grayed out in the background). I have seen a similar technique used on a number of websites recently for display images as well. I'm wondering what technology/code they use to do this? It's open source - use the source, Luke. Look in wp-admin/js/theme-preview.js preview_theme() Start preview theme output buffer. Description Will only perform task if the user has permissions and template and preview query variables exist. Source function preview_theme() { _deprecated_function( __FUNCTION__, '4.3.0' ); } The Customizer JavaScript API In WordPress 4.1, newly-expanded JavaScript APIs were introduced for all customizer objects. The entire Ja...