Recent answers to Ctrl + F find/search function not showing matcheshttps://support.mozilla.org/km/questions/13032162020-09-06T09:13:09-07:00Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add2020-09-06T09:13:09-07:00cor-elhttps://support.mozilla.org/km/questions/1303216#answer-1347528<p>Start Firefox in <b>Safe Mode</b> to check if one of the extensions ("3-bar" menu button or Tools -&gt; Add-ons -&gt; Extensions) or if <b>hardware acceleration</b> or <b>userChrome.css</b> is causing the problem.
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<ul><li>switch to the DEFAULT theme: "3-bar" menu button or Tools -&gt; Add-ons -&gt; Themes
</li><li>do NOT click the "Refresh Firefox" button on the Safe Mode start window
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<ul><li><a href="https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode" rel="nofollow">https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode</a>
</li><li><a href="https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems" rel="nofollow">https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems</a>
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<p>You can check for problems with preferences.
You can delete possible user.js and numbered prefs-##.js files and rename/remove the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in current Firefox releases.
</p><p>You can use the button on the "Help -&gt; Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the <b>about:profiles</b> page.
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<ul><li>Help -&gt; Troubleshooting Information -&gt; Profile Folder/Directory:<br>Windows: Open Folder; Linux: Open Directory; Mac: Show in Finder
</li><li><a href="https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data" rel="nofollow">https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data</a>
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