Did you try to disable hardware acceleration in Firefox?

Does this only happen in the Firefox 34 Nightly build or do other versions (33.0a2 Aurora, 32,0 Beta, 31.0 release) also crash?

• Tools > Options > Advanced > General > Browsing: "Use hardware acceleration when available"

You need close and restart Firefox after toggling this setting.

• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes
• https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

You can use one of these to start Firefox in Safe Mode:

• On Windows, hold down the Shift key while starting Firefox with a double-click on the Firefox desktop shortcut
• On Mac, hold down the Options key while starting Firefox
• Help > Restart with Add-ons Disabled

• https://support.mozilla.org/kb/Safe+Mode

I Didndt disable the hardware accelaration on firefox forgot that.

i have last drivers for my ATI card (R9 270x)

disabling H.A. solved :)

Hello,

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