XFCE 4.10 panel auto hide feature stops working on occasions

I realize that this won't give you a permanent fix for your issue. But, this is a workaround that I have found useful and will keep you from having to reboot constantly.

Since upgrading to Xfce 4.10, I have had an issue with window decorations not always being visible upon log in. I have used the following command to fix it:

You can reset your Xfce desktop, without restarting, using the command xfwm4 --replace.

Or, you can try this to just reset the panels:

Resetting the panels can be done with xfce4-panel -r.

Finally, there is an open bug with the auto-hide feature in Xfce 4.10, although it has only been confirmed in Ubuntu 12.10.

Update 2017-02-07: This appears to have been fixed in Ubuntu 15.10.