Today I learned a nifty new thing. One of our clients is trying to serve a FireFox extension from their site. In order to do this, we had to add a new MIME type to IIS (.xpi = application/x-xpinstall). Now when they were testing in FireFox by clicking the download link it would open a new tab that was blank and stop there. If they opened the download link in IE, it would run correctly and start the download approval process. Well, if IIS is serving the download to IE, then it should be serving it to FireFox, so I didn’t think IIS was the culprit. One thing I noticed was that the download wasn’t signed when I saved it using IE. One site on FireFox info, Rietta, said that if the app isn’t signed then there will be a pause before downloading to let you know the app wasn’t signed. This got me thinking. I clicked on the download again and this time I waited, and waited, and waited some more. Well, it didn’t download. Hmmmm I thought what about the FireFox security settings? I looked at tools\options\security and I unchecked the “Warn me when sites try to install ad-ons”. I shut down FireFox and restarted it. I hit the download and this time it worked. So, lesson learned, if you are trying to serve FireFox extensions that use .xpi you need to have your MIME type setup on the server and you should have your extension signed. (Or your security turned off, which is NOT a good idea. 😉 )
Robba