Created attachment 9480 Solid colour selected as desktop background In section Desktop | Background , applying a solid color, be option 'Apply to all workspaces' set or not, does not operate, thus a wallpaper in place persist in place.
You have to set the Style option to 'None'.
Thank you. What could be an accurate section to report against about logins to XFCE?
Would that be an issue with Xfce or the login manager? If you try to solve a configuration problem, please ask for help in our forum first. https://forum.xfce.org/
Log in though GDM no longer allowed once switched from a Gnome session.