Backgroundd is a lightweight ChromeOS extension that allows users to easily rotate their wallpaper images. With this extension, your ChromeOS wallpaper will be automatically set to an image downloaded from a configurable URL every 60 minutes. You can even customize the rotation interval to suit your preferences, with the minimum interval being 5 minutes.

Please note that after installing the extension, it may take some time for the wallpaper to update, as the spotwall app running on the Azure free plan is CPU limited.

Additionally, the developer has included a small Python script in the repository that serves random images from the directory it was started in. This script can be run on Crostini or on a different computer, providing users with more flexibility in managing their wallpaper rotation.