I've recently encountered an Xfce issue that wasn't apparent until now. Here's some background:
My wife has Alzheimer's dementia, as I've mentioned before, and she uses her laptop to play solitaire games (only). When her budget laptop failed and needed to be replaced, I loaned her one of my DEL Latitudes to use. It's the one with Xfce on it, and for her purposes, I didn't see the need to install Plasma, as on her own laptop. I just left it on Xfce and created a user for her. Spider Solitaire, Shisen-Sho, and Mahjongg don't care which DE they're run on.
So that laptop now displays my name and her name on the logon screen. Clicking on her name does nothing at all. In order for her to log on, she needs to click on MY name, and after the textbox for entering my password appears, select her name instead. Only then will another textbox appear where she can input HER password.
It took me a while to figure out what I needed to do to get her logged on. In fact, I found out by accident. Although it's not a difficult workaround, I imagine folks running Xfce, and who add a second user account, might be puzzled for quite a while until they similarly discover the workaround by accident.