As newer versions are released the less support for legacy extensions/add-ons there is remaining. Goto "Help" -> "Restart with add-ons disabled" and test.

Further you can refresh Firefox by following this: https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings

If you have submitted crash reports then please post the IDs of one or more recent crash reports that start with "bp-".

• bp-xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx

You can find the report ID of recent crash reports "on the "Help -> Troubleshooting Information" (about:support) page".

• click the "All Crash Reports" button on this page to open the about:crashes page and see all crash reports.

Alternatively you can open about:crashes via the location/address bar.

See also:

• http://kb.mozillazine.org/Mozilla_Crash_Reporter
• https://support.mozilla.org/en-US/kb/Mozilla+Crash+Reporter