How to FIX Firefox Extensions / Add-ons stopped working

[c627627]

Over the weekend, a mass of Firefox extensions was wiped out due to incompetence of people in charge.

In 2019 About 10% of Firefox users still used Firefox 52.9 ESR, the final version of Firefox on which many old extensions/Add-ons could still be used on. In May of 2019, many of the old extensions were disabled due to a bug which affected all Firefox versions.
This is the Fix for Firefox 52.9 ESR:

Save the block below including the BEGIN and END lines in a text file with the extension .pem, in other words name the text file something like FirefoxFix.pem

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-----END CERTIFICATE-----


Tools > Options > Advanced > Certificates > View Certificates > Authorities > Import... > Brose to the saved .pem file and Open it > CHECK every box > OK > OK

type
about:config
in the address bar then paste the name in search box or scroll down to:
devtools.chrome.enabled
Double click on it to set it to True.
Restart Firefox

CTRL+SHIFT+J to get the Browser Console:
Paste these two lines:
Components.utils.import("resource://gre/modules/addons/XPIProvider.jsm");
XPIProvider.verifySignatures();
YOU MUST PRESS Enter AFTER YOU PASTE THESE LINES.

Close all Firefox windows.

In case of problems, simply Disable & then Enable the problem Add-on / extension.

Edited certificate can be seen under:
Tools > Options > Advanced > Certificates > View Certificates > Authorities >
Mozilla Corporation
signingcal.addons.mozilla.org

 

[RollingThunder]

Yep,

I was hit with Ghostery and Adblock incompatibility because I do a lot of cruising on the old Vista64/Firefox machine. I use Firefox up to the the last compatible version (52.9) for non W10 machines. There are some alternative ad blockers which I am using now that work fine.

By the way when Ghostery an Adblock were disabled the added quickness of my computer was noticeable so they are some of the culprits of slowing a machine down. I replaced Adblock with Adguard from Major Geeks without any noticeable slowdown.

 

[Mpegger]

Or you can update to 66.0.4. The fix is up already, though I do understand if you are on a older version this is not of much help. I can't picture too many old extensions that still require such an old version though.

 

[RollingThunder]

Or you can update to 66.0.4. The fix is up already, though I do understand if you are on a older version this is not of much help. I can't picture too many old extensions that still require such an old version though.

Yep, I don't expect compatibility forever with the old Vista64 but all add ons work fine on my W10 machine with updated Firefox.

C6,

Are you saying Firefox will post a fix for Firefox 52.9 ESR or are we on our own to fix this with your post above?