Hello,

To find the correct solution to your problem, we need some more non-personal information from you. Please do the following:

1. Use ONE of these methods to open the Firefox Troubleshooting Information page:
   • Click the menu button , click on help and select Troubleshooting Information.
   • Type about:support into the Firefox address bar and press the enter key.
2. At the top of the Troubleshooting Information page that comes up, you should see a button that says "Copy text to clipboard". Click it.
3. Now, go back to your forum post, right-click in the reply box and select Paste from the context menu (or else click inside the reply box and press the Ctrl+V keys) to paste all the information you copied into the forum post.

If you need further information about the Troubleshooting information page, please read the article Use the Troubleshooting Information page to help fix Firefox issues.

also this instruction guide may help?

Firefox hangs or is not responding - How to fix

From what I have been reading from other posts on this forum, the issue may be caused by the clear history settings. It was suppose to have been fixed in v30.

Type about:preferences#privacy <enter> in the address bar.

The button next to History, select Use Custom Settings.

At the bottom of the page, turn on Clear History When Firefox Closes. At the far right, press the Settings button. Turn on ONLY Cache and Form And Search History leaving the others off.

This is not a cure but will make it easier if Firefox locks up in Windows. https://support.mozilla.org/questions/997866 {web link}

batch