User-Agent: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O 10.4; en-US; rv:1.9b1) Gecko/2007110903 Firefox/3.0b1 Build Identifier: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O 10.4; en-US; rv:1.9b1) Gecko/2007110903 Firefox/3.0b1 If firefox 3 is set to be the handler for a type of link (like news://) then it can enter into an infinite loop and continue to open tabs until exited. Reproducible: Always Steps to Reproduce: 1.Click on a link to a newsgroup (like the link at http://wiki.mozilla.org/Places to news://mozilla.dev.apps.firefox) and set it to open with whatever. 2. Go to the applications preference pane and set this link type to always open with firefox 3. 3.Go back to http://wiki.mozilla.org/Places and click on the link. Actual Results: Firefox 3 opens an unending stream of tabs (caught in infinite loop) Expected Results: Firefox 3 should detect that it is being called as the helper application and avoid the infinite loop. Maybe warn the user.

Can you reproduce with the latest Minefield? I can't reproduce this with a trunk nightly but I *do* see it using Firefox 3b1. http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-trunk/

I see this in nightlies on Linux. Nominating for blocking-firefox3, but I suspect this is really just wanted-firefox3, because one has to try pretty hard to make this happen.

Yup, I can still reproduce it with the nightly from the above link (build info below). If you are running Minefield on the same profile as you did with Firefox 3b1 then you are going to make sure the news links are set to open with Minefield rather than Firefox 3b1. In particular I reproduced this with the nightly as follows. 1. Start the nightly with a clean profile. 2. Navigate to http://wiki.mozilla.org/Places (or this page) 3. Click on the link news://mozilla.dev.apps.firefox 4. Click on choose an application in the dialog and navigate to the executable/app bundle for the currently running version of firefox (e.g. Minefield). 5. Check the always open with checkbox and hit ok. Now tabs will continue to open until you quit the browser. Since firefox is merely sending the URL to itself this will require an explicit check to prevent the loop. --------- Build ID: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O 10.4; en-US; rv:1.9b2pre) Gecko/2007112604 Minefield/3.0b2pre ID:2007112604)

This has been around forever. Its a tricky edgecase, but users can undo the problem.