When you install the .NET Framework 3.5 SP1 that was released today, and you're running Firefox 3 as your browser du choix, the next time you run Firefox you'll get the Add-Ons dialog showing you that a new add-on has been installed.
Funny that, I don't remember okaying that particular choice, but anyway. I'm about to install SP1 on another machine, so I'll look out for it.
This add-on provides click-once support for Firefox and also will report back to whatever web server is asking the latest version of .NET that you're using. Back in May, Scott Guthrie reported that this would be part of the SP1 beta, although it's fun to try and find it:
ClickOnce Client Application Deployment Improvements
- ...blah blah...
- FireFox browser extension to support Clickonce installations using FireFox browsers
Just a friendly heads-up from your homies at DevExpress...