I've developed a couple Firefox/Mozilla extensions in the past. As Second Life is going to be using the Mozilla engine for the in-game web browser, will SL support extensions?
I guess this question can further be defined as:
1) if yes, will it be possible to install extensions through webpages displayed in-world(on a prim for example)
2) OR will we be able to use something like llLoadURL() to install extensions
3) OR will SL Mozilla support extensions, but they must be manually installed somewhere into the SL local installation on your computer
4 if no, well then I guess there's no support for XUL extensions in the future.
I think if 1-3, then there are *lots* of cool things that builders can create to extend the SL experience.
Geuis