Suspend/Resume triggering multiple screen lockers
I would like to be able to enter my password just a single time whenever I Resume my laptop (running XUbuntu 18.04) from being Suspended. I am using XScreensaver instead of gnome-screensaver, and LightDM for my login manager (with lightdm-gtk-greeter, if that helps anything), and right now I have xfce4-power-manager set up to "Lock screen when system is going for sleep", as the checkbox says.
Unfortunately, this is, in sequence, locking the screen with both the LightDM greeter and XScreensaver. If I tap a key on the keyboard at the exactly right time, I can dismiss the screensaver before the power manager gets to locking the screen with XScreensaver, but it should not be doing this.
The version I'm currently running is 1.6.1-0ubuntu1, so I don't know if there's a later version available that has this bug resolved, but I presently do not have a repository listed that gives me anything later.