hello, could you provide your latest few submitted crash reports? please enter about:crashes into the location bar, copy the latest few report ids from there starting with bp- & paste them here into a forum reply. this will give us a better understanding what may be triggering those crashes.

id1:bp-65878c39-46cf-4e16-b5c1-b0ac62141128 id2:bp-0bbcc459-f285-4d10-a335-35a782141128 id3:bp-b803ca13-0acc-4162-8b51-4b7b92141128

Those reports are about hangs in the Shockwave Flash plugin (NPSWF32_15_0_0_223.dll).

You can check for problems with current Shockwave Flash plugin versions and try this:

• check for updates for your graphics drive drivers
  https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration
• disable protected mode in the Flash plugin (Flash 11.3+ on Windows Vista and later)
• disable hardware acceleration in the Flash plugin

See also:

• http://kb.mozillazine.org/Flash#Troubleshooting