Web wallpapers can leverage a number of extra features from Wallpaper Engine. You can add custom properties, build audio visualizers, and read the user settings to make sure your wallpapers behaves as the users wishes it to.
You can access the Chromium Devtools for your web wallpaper. First, set up a debugging port in the Wallpaper Engine general settings like port 8080. Then you need to download a compatible CEF browser from here: http://opensource.spotify.com/cefbuilds/index.html
Download the 'Sample Application' for Windows 32, currently any with version 79 should work.
Open the sample application and then open the Devtools by navigating to http://localhost:8080 inside the sample application.
(You might be able to use your normal browser instead of the sample application, but Google has not created the Devtools with high compatibility so there is no telling if your browser can support them. Chrome gets updated extremely often and the Devtools can break again and again.)
After importing your web project you can publish it.