My current thoughts, and plans ....
Try re-installing Mozilla. I think it a long shot, but is easily enough accomplished.
If that does not work, try reinstalling Firefox too. See if I can get *any* behavior change.
If that doesn't work, I'll just make a note not to use the XP box for cPanel! Nope, not going to IE for tasks other than testing. Pfffffffftttthhh
Maybe I'll install Opera, or some other. Lot's of good browsers.
Thanks for all your comments. Was hoping someone would respond with "Yeah, we've heard of that one. Just change this setting, and ... ", or something else easy. Ah, well ... Next time.
TCH has certainly been a positive experience so far!