Mike, thanks. I think I installed it, now I'm checking to see if it works. I intenshunally misspelled a word.
Nope. The icon is in the toolbar, and it showed up as an active icon as soon as there was a text entry box on the screen, but when I clicked the icon, it said, "TypeError: dictList[0] has no properties." Then, it came up with a spell check pop-up, and said there were no errors. As far as I know, I installed both the extension and the dictionary.
Guess I'll fool with it later. That's one of the problems with this experimental stuff -- it takes too much time away from actually using the computer.. Back in my early guru days, while I was learning more about the early PCs than most other people knew (early '80's), I ate up this kind of thing. Then, I discovered that my friends were actually using their computers instead of fooling with them, and they were more successful than me.