Recent answers to Have the latest Firefox, but the menu button doesn't show "sign in to sync"https://support.mozilla.org/kn/questions/10319502014-11-20T04:41:21-08:00what do you see in the Sync tab in Options > Sync?
Start Firefox in Safe Mode to check if one o2014-11-20T04:41:21-08:00cor-elhttps://support.mozilla.org/kn/questions/1031950#answer-655617<p>what do you see in the Sync tab in Options &gt; Sync?
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<p>Start Firefox in <u><a href="/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode" rel="nofollow">Safe Mode</a></u> to check if one of the extensions (Firefox/Tools &gt; Add-ons &gt; Extensions) or if hardware acceleration is causing the problem.
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<ul><li>Switch to the DEFAULT theme: Firefox/Tools &gt; Add-ons &gt; Appearance
</li><li>Do NOT click the Reset button on the Safe Mode start window
</li></ul>
<ul><li><a href="https://support.mozilla.org/kb/Safe+Mode" rel="nofollow">https://support.mozilla.org/kb/Safe+Mode</a>
</li><li><a href="https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes" rel="nofollow">https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes</a>
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