I'm using Xfce 4.10 on Fedora 19, fully updated. I have xscreensaver installed and have set it not to lock the screen.
Recently, on a Fedora help forum, there was a question about logging out under Xfce, which I answered. Today there was a comment from another member suggesting that ^Alt-Del would work. I tried it to see what would happen: the screensaver came up and locked the screen. I had the choice between giving my password or logging in as a different user.
I don't know about anybody else, but I had no idea that this would happen. Yes, it's convenient for some people, but I'm the only person who ever uses this computer and I have no reason to lock the screen when I'm away. (If I did, I'd just configure xcreensaver that way.)
Hunting around, I ended up looking in the xfce Settings Editor. Under xfce4-keyboard-shortcuts, the default action for this combination is xflock4. I've deleted the command and checked: for this, at least, you don't need to log out and back in; it takes effect right away. I don't know if anybody else will care about this, but I did think that it was worth documenting.
Registered Linux user #470359
Permanently recovered BOFH
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