Recent answers to How do I get tabs back under toolbar like it was before. I for one do not like it at the top the way it is.https://support.mozilla.org/ar/questions/12584942019-05-05T11:42:48-07:00I think the problem is that all your add-ons became disabled?
A critical certificate Firefox uses to2019-05-05T11:42:48-07:00jscher2000https://support.mozilla.org/ar/questions/1258494#answer-1219751<p>I think the problem is that all your add-ons became disabled?
</p><p>A critical certificate Firefox uses to verify extension signatures expired at midnight May 4th (GMT). The first time your Firefox ran its daily signature verification after that time, it failed and most extensions were disabled. Your Firefox needs an updated certificate installed to re-enable them.
</p><p>Currently there are updates for Firefox 60 ESR and Firefox 66. There was a note on Twitter that Mozilla may release something for unsupported older versions. We don't know about any schedule for that yet.
</p><p>For the time being, you would need to install the new certificate for verifying extension signatures a different way, such as installing manually. For an unsupported approach, see: <a href="https://support.mozilla.org/questions/1258165#answer-1218833" rel="nofollow">https://support.mozilla.org/questions/1258165#answer-1218833</a>
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<p><em><strong>No Add-on Method</strong></em>
</p><p>You could use a <strong>userChrome.css</strong> file to move your Tabs bar below your main Navigation Toolbar and Bookmarks Toolbar, but that does take some time to set up.
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