How to Enable Disabled Firefox Add-ons
In this video tutorial, you will learn how to enable Firefox extensions or add-ons that have been disabled. In Firefox 43 and above, Mozilla started enforcing Extension Signing in order to counter malicious Firefox add-ons. In doing so, they have disabled all add-ons that do not meet this signing requirement.
If you are using Firefox 43 and above (2016), you will find that some of your add-ons are disabled by default. Mozilla has provided a Firefox Preference to temporarily override this Extension Signing using “about:config” via the configuration editor. The preference that you need to change is “xpinstall.signatures.required”. Essentially, you need to change the value of this preference from “true” to “false”.
More about Extension Signing: https://wiki.mozilla.org/Add-ons/Exte...
NOTE: The above is only a temporary measure and Mozilla will do away with this Firefox Preference in Firefox 46.
UPDATE (04-May-2019): There is currently a bug that has disabled many Firefox add-ons. Mozilla is aware of this and has implemented a temporary fix via Studies. The team is working on a more permanent fix. You can check updates here: https://blog.mozilla.org/addons/2019/...
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