xfdesktop wrongly complaining "failed to set the background".

I have set up xfdesktop to set the background wallpaper from a folder, and change every 5 minutes.

Each time the wallpaper is changed, the following error message appears in the /home/user/.local/share/sddm/xorg-session.log:

** (xfdesktop:3062): WARNING **: 21:54:08.828: Failed to set the background '/home/user/images/image111.jpg': GDBus.Error:org.freedesktop.DBus.Error.InvalidArgs: No such interface “org.freedesktop.DisplayManager.AccountsService”

The message, however, is wrong. The image is set up as intended.