Hello First, enable your browsers Health Report by going to Menu > options > Advance > Data Choice and enable Health Report https://support.mozilla.org/en-US/kb/firefox-health-report-says-your-browser-is-slow

Also check from Task Manager if your FireFox is taking too much RAM if Yes then consult this page https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-ram

If not, then check this support Page https://support.mozilla.org/en-US/kb/firefox-does-not-work-common-fixes

Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac Options) key, and then starting Firefox. Is the problem still there?

i have a lot of bookmarks around 150 of them is that causing this problem

FredMcD said

Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac Options) key, and then starting Firefox. Is the problem still there?

valasudurai said

i have a lot of bookmarks around 150 of them is that causing this problem

The number of bookmarks should make no difference. But use this;

Places Maintenance {web link} Allows to run Maintenance tasks on the database that drives Places, the bookmarks and history module behind Firefox.

These will also be helpful;

Bookmark Duplicate Cleaner {web link} Scans for bookmark duplicates and allows you to delete them

Bookmarks Checker - check for bad links {web link} Check favorites for broken or bad links. It checks for bad links and displays a report if it finds something. Check for 404 links, timeout links.

Still I am facing the same problem do you have any idea to fix like other browser says the page was not responding to you want to kill but the firefox only says do u want to stop the plugin but it takes really long time to return to the normal state pls help also it just hanging for a long time the one page causing the all the website hangup also we are not able to work further with other site

I had a stroke and can't be as helpful as I could. I've called the big guys to help you. Good luck.

Ok the problem was fixed automatically after updating the latest beta version you know i must explain it better

If i have a four tab in Firefox if i close the the one tab website other three takes 3 sec to go to that page it also hanging longer time depending upon the webpage also if i don't have a any page also act like this

thanks for your help the problem was fixed i not get the problem as i mentioned but the problem was occur in rarely so thanks for your help

Still the problem was there i don't know why it happen but it was very less compared to the earlier one but it needs to be good

Hi valasudurai , Sorry for the delay, I understand that there is a page that is not responding because a plugin is taking a long time to load.

I do not see any plugins listed in your troubleshooting information. It is possible to set it to "Always Ask" so that the page loads and you then allow it to load.

Since you mentioned it was fixed, and that is sometimes happens later I will assume that it is still sometimes happening. If you saw in Safe Mode that it does not happen all the time this is an indication that it might be caused by an add on. Try to disable each one by one after updating them to make sure its not an add on.

i think the adobe flash cause this problem can i turn off the plugin and i will check how the firefox perform

This should do the job, and leave flash if you want it.

Flash block {web link} Never be annoyed by a Flash animation again! Blocks Flash so it won't get in your way, but if you want to see it, just click on it