LANTERN - That option doesn't seem to exist in my (latest) Firefox version - it's all drop-down stuff, unlike some other browsers.
BUSHFIVA - Control-Shift-Delete worked beautifully . . . or so I thought. Afterwards, I exited Firefox . . . but the buggers were back when I opened it up again. I've always used "Everything" when clearing history - it gets rid of everything else but not these.
I'll just have to learn to ignore them - unless there's another solution.
Thanks to both of you, anyway.