Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

• Switch to the DEFAULT theme: "3-bar" menu button/Tools > Add-ons > Appearance
• Do NOT click the "Refresh Firefox" button on the Safe Mode start window

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

Create a new profile to test if your current profile is causing the problem.

See "Creating a profile":

• https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles
• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.

• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

The System Detail list next to the question shows that you run an older Firefox 44 version that is no longer supported with security updates. Always update Firefox and Add-ons to the latest versions to get all security fixes.

Please update to the current Firefox 45.0.1 release.

• Help > About Firefox

• https://support.mozilla.org/kb/update-firefox-latest-version

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