i didn't face any issue.

Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:28.0) Gecko/20100101 Firefox/28.0 ID:20131105030206 CSet: 770de5942471

its my system details. could you provide your system details.

We're sorry to hear that Firefox is crashing. In order to assist you better, please follow the steps below to provide us crash ID's to help us learn more about your crash.

1. Enter about:crashes in the address bar (that's where you enter your website URL) and press Enter. You should now see a list of submitted crash reports.
   
   
2. Copy the 5 most recent crash ID's that you see in the crash report window and paste them into your response here.

Thank you for your help!

More information and further troubleshooting steps can be found in the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article.

The not supported Win64 Nightly builds tends to be the most crash prone of Nightly builds compared to for other OS.

Anyways some other users are getting crashes on recent Nightly test build at http://forums.mozillazine.org/viewtopic.php?f=23&t=2766377

Juke2706,

Is there any particular reason that you aren't using the standard 32-bit Release version of Firefox 25 on that Windows PC?

At this point in time the Win-64 Nightly version isn't being actively developed. Currently it is primarily being used to make sure that work being done on the 32-bit pre-release versions (Nightly 32, Aurora, and Beta on Win OS's) don't break something that would be hard to fix once development on the Win-64 Nightly resumes. And as James alluded to, right now the Win-64 Nightly isn't really all that stable. But at least there are "nightly" updates, so that might change tomorrow.