via wptavern.com => original post link
WordPress Sandbox, an experimental project that uses WebAssembly (WASM) to run WordPress in the browser without a PHP server, has been chugging along steadily since Automattic-sponsored core contributor Adam Zieliński introduced it earlier this year in September.
Zieliński published three new updates to Twitter this week, demonstrating the project’s potential to provide an in-browser IDE for plugin development along with a quick way to spin up a test environment for themes and plugins.
In the first example, he shows how the project could be used to test-drive themes from WordPress’ Themes Directory right in the browser. Clicking the demo URL will launch a site with the Pendant theme active, but the theme can be changed to another from the directory by appending a different theme name to the end of the URL. All your changes made on the demo are private and disappear after a page refresh. With a few improvements, this could be transformative for previewing themes on WordPress.org.