Outlining a possible roadmap for the Customizer

Planning for the future is a necessary and important part of the WordPress development process. As we consider the future of WordPress – both as a whole and individual features – we publish proposed roadmaps to encourage greater discussion and give insight into the coreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress. team’s thought process.

The process of creating a roadmap is just as important as the vision behind it and the final roadmap itself. This process gives the entire community an opportunity to research and document history, define what specific items can be accomplished to bring us closer to the vision, and outlines how those tasks fit together within a possible timeframe.

What follows is a potential roadmap for the Customize component. If you’re interested in the future of live preview in WordPress, now is the perfect time to get involved and leave your feedback.


A couple of months ago, the WordPress lead developers met with the maintainers of the Customize component to discuss the future of live preview in WordPress. The goal of the chat was to come up with a potential roadmap for both the component and for how live preview can improve the user experience of WordPress for all users.

The ultimate goal of live preview in WordPress is to create user trust and remove the “save and surprise” inherent in some of the backend features.

After a lot of discussion, the group decided to target the following goals over the next two years:

  • Considerably improve performance.
  • Continue iterating on current live preview features to ensure they are solid and as easy-to-use as possible, including theme browsing and installation, menus, and widgets.
  • Experiment with new and different user interfaces. If we were creating live preview today, what would it look like? In what ways can we ease the feeling that you’re looking through a “porthole”?
  • Removal of the ambiguous mode. Currently, the CustomizerCustomizer Tool built into WordPress core that hooks into most modern themes. You can use it to preview and modify many of your site’s appearance settings. is contained in a sidebarSidebar A sidebar in WordPress is referred to a widget-ready area used by WordPress themes to display information that is not a part of the main content. It is not always a vertical column on the side. It can be a horizontal rectangle below or above the content area, footer, header, or any where in the theme. without the adminadmin (and super admin) toolbar, but ideally there is the admin and the theme, and no in-between. One direction this may go is enabling “Customize” on the front end to immediately load the Customizer controls.
  • Experiment with a guided new user experience (NUX). Live preview lends itself to site setup. How can we improve the live preview experience and combine it with the NUX? Consider a “setup wizard” use case and ensure the flow has no dead ends, i.e. users can customize everything in one.

Those overall goals for live preview in WordPress can be rewritten into some specific features that are in development or planned for the future of the Customize component. These include:

  • Transactions. This re-architecture of some of the Customizer internals improves compatibility with themes by loading the preview using a natural URLURL A specific web address of a website or web page on the Internet, such as a website’s URL www.wordpress.org, and allows Ajax requests or even REST APIREST API The REST API is an acronym for the RESTful Application Program Interface (API) that uses HTTP requests to GET, PUT, POST and DELETE data. It is how the front end of an application (think “phone app” or “website”) can communicate with the data store (think “database” or “file system”) https://developer.wordpress.org/rest-api/. requests to be previewed. It also allows the preview to be viewed independently of the Customizer, so changes can be shared for others to review. See #30937.
  • Selective refresh. Only a piece of the page will need to be refreshed when this backend feature is implemented. (Formerly known as “Partial Refresh”.) Currently, this is available for menus in the Customizer. This eliminates duplication of display between PHPPHP The web scripting language in which WordPress is primarily architected. WordPress requires PHP 5.6.20 and JSJS JavaScript, a web scripting language typically executed in the browser. Often used for advanced user interfaces and behaviors., keeping it DRY. See #27355.
  • Concurrency. Allows for “locking” settings using the Heartbeat APIAPI An API or Application Programming Interface is a software intermediary that allows programs to interact with each other and share data in limited, clearly defined ways., improving the overall user experience by preventing users from overwriting each other’s changes. See #31436.
  • RevisionsRevisions The WordPress revisions system stores a record of each saved draft or published update. The revision system allows you to see what changes were made in each revision by dragging a slider (or using the Next/Previous buttons). The display indicates what has changed in each revision.. Enables pluginPlugin A plugin is a piece of software containing a group of functions that can be added to a WordPress website. They can extend functionality or add new features to your WordPress websites. WordPress plugins are written in the PHP programming language and integrate seamlessly with WordPress. These can be free in the WordPress.org Plugin Directory https://wordpress.org/plugins/ or can be cost-based plugin from a third-party developers to add features like draft, roll back, and scheduled changes (e.g. “change my background on January 1”). This builds upon transactions, as the setting changes are staged in a transaction, and this facilitates settings to be revisioned and for settings to be scheduled. See #28721, #31089.
  • Theme installation. Iterates on and completes the theme browsing experience.
  • Responsive preview. Iterates on the concept of live preview by giving users a better idea of what their site will look like on other devices. See #31195.
  • Bootstrapped Customizer. Lazy-load the Customizer into the current frontend view without having to leave the page. With selective refresh implemented, inline controls and frontend bootstrapping would be possible since full-page refreshes would no longer be required.
  • Improvements for both touch and small devices.

Beyond those features, the group identified some specific changes that should be prioritized, in conjunction with the features planned:

  • The sliding animation between panels should feel more like “moving panels” (see: iOSiOS The operating system used on iPhones and iPads.).
  • Keyboard navigation should be consistent and clear.
  • Identify “dead ends” in the interface and remove them, when possible. For example, prior to menus in the Customizer, it was not possible to customize that aspect of your site’s design with the Customizer.

The concepts surrounding live preview and the Customizer have been in development for a long time. Many of the concepts from Elastic Theme and the Visual CSS Editor have been incorporated over time. Over the next few years, experimentation with these concepts will likely take place in feature plugins. For example, this team may experiment with inline content editing, where it makes sense in the context of customizing a site. Another path for exploration is simple theme customization – e.g. change the headerHeader The header of your site is typically the first thing people will experience. The masthead or header art located across the top of your page is part of the look and feel of your website. It can influence a visitor’s opinion about your content and you/ your organization’s brand. It may also look different on different screen sizes. font, change the sidebar color, or change the width of the sidebar.

As with all components and new features, we shouldn’t be afraid to experiment and fail and should continually push for new experiments and ideas, especially in the context of feature plugins. Further, some of the above experiments may not make it into core, but are meant as a general direction that live preview should take in WordPress.

Taking these features together, below is a sequence outlining a possible roadmap for live preview and the Customize component in general, along with estimated targets. Please note that this is a proposed roadmap and is entirely dependent on contributor involvement. Additionally, many of these things will take place in a feature pluginFeature Plugin A plugin that was created with the intention of eventually being proposed for inclusion in WordPress Core. See Features as Plugins. prior to core inclusion.

  • Partial refresh. Performance Improvements. (Target: 4.4)
  • Responsive Preview. Transactions. (Target: 4.5)
  • Concurrency. Revisions. Theme Install. Beginning of NUX wizard. (Target: 4.6)
  • Focus on touch screen / small device improvements. (Target: 4.7)
  • Developer API improvements based on feedback from plugin developers. (Target: 4.8)
  • Improved UIUI User interface after experiments in 2016. NUX “wizard mode.” (Target: 4.9)

Live preview is one of the most critical features in WordPress as we continually combat “save and surprise.” The Customizer in its current form provides an improved user experience to WordPress users when customizing their site’s design. Each feature mentioned above is a continuation of the live preview concept, building and improving upon the Customizer.

Everything above is just a proposal and we need your feedback to ensure it is the right direction. If you’re interested in any of the above, comment here with your feedback, or join the team in #core-customize.

This post was a collaboration between @helen, @nacin, @mark, @celloexpressions, @samuelsidler, and yours truly.

#customize, #roadmap, #roadmaps