If you are running Chrome 67 on your Chromebook, there is now a flag available to you that will allow you to enable the still under construction new wallpaper picker. The new picker replaces the old style picker which has been in the platform since, well, forever. It brings a refreshed, Material Design look to the picker and eventually will marry up with the backdrop wallpaper changer that is found in Chromecast.
That’s where the under construction part comes into the equation. Right now there is a commit in the Chrome OS Gerrit that points to a new wallpaper that is enabled by default and that it will marry up with Chromecast. The idea is that your Chromecast and your Chromebook will have the same look and feel and will be drawing from the same service in the background to give you your wallpaper options.
If you want to enable this new picker, without the Chromecast syncing bit, you can do so through a flag in Chrome OS. If you go chrome://flags in the browser, search for “New Wallpaper” to find the #enable-new-wallpaper-picker flag. Once you enable it and restart Chrome, you will get the new look picker.
As you can see, you have a lot of different categories to chose from as your wallpaper on your Chromebook and, of course, can select a wallpaper from your local storage or Google Drive it you want to go that route.
Eventually, likely in Chrome 68 next month, this feature will be the default setting but why wait when a flag is available today?