Thread: Add-ons not working due to certificate expiration

One more question: FF will re-check certifications 24 hours after the last one?
Or when does it will do that?
How often?

Owh, here I’m using Windows, not Linux.
No terminal available.
How to do that on Windows 7?

No you need to run the commands.

Nothing will happen till then.

This what triggers the program to reactivate things… Soon as the 2nd one is run… my Ghostery button came back, my ad block… and all the the cookies that had gotten through erased.

Can’t speak to non Linux systems. Works here. 32B Linux FF 56.0.2


Or you can wait and wait and wait for a “trust chain” verified solution from moz… we are 8+ days and counting? You want to risk it that long on non Linux? I don’t even on Linux. I had to move to another browser till this solution came up, and no its not spyrome either.

Fix it, move on with life, and get back on track.

To all the others on V56 or less FOLLOW HEURSTICS POST! Save your self the grief, get your browser back. Move on… Don’t matter what OS Linux or non OS you are using don’t risk it with the garbage out there.

I already have the solution here.
My extensions are working fine.
I just want to better understand how and when FF makes its checks.
Thanks anyway.

I use a webpage:


Yes, I’ve found that minutes ago. :+1:

I have imported this, followed by the two commands in the console from the other post.
As of now, my addons are back and I hope it stays this way.

Thank you for your effort and help!


For anyone who might prefer an extension:

Very good! :slightly_smiling_face:

Thank you so much for your post. That did the trick for me. Even tho’ the “studies” didn’t successfully install the updated certificate, following your instructions, it’s all good. I found the Mozilla cert which was not there previously.
FF did NOT disable after add-ons after 24 hours. So far, so good.
And I was able to install an update to an add-on which could not previously.

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I installed the extension from the bugzilla attachment for my version (52-60)…my version is 56.0.2, and all add-ons are back up and running again! I had to restart Firefox to get them enabled after I installed the hotfix, but all is good now. I’ll report back if it doesn’t hold or if I notice any other issues, but for now looks like all is well. :slight_smile:

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Affected users may wish to subscribe to this:

– I’m about to add a comment there …

do this then once you do that you can add extensions again

FAIL: Certificate issue causing add-ons to be disabled or fail to install

Worst of it is firefox does not provide a way for the user to continue to use the supposedly bad add-ons turning this bug from bad to worse. There is no technical reason which would prevent these add-ons from working.

Hotfix is deployed through about:studies but after allowing studies it did not yet show up for me. Official quote: ‘It may take up to six hours for the Study to be applied to Firefox.’ What a hotfix lol.
The general fix is in the next version 66.0.4 but having to wait to get basic functionality back sucks.

Update: Fortunately it took only about 30 minutes for the study to be added after I enabled studies.
I don’t like that Firefox installs studies without informing you that a new study was installed, or even better: for privacy conscious people ask if they want to participate on a per-study basis (I would enable studies if it would be opt-in).
It also provides close to no information about the studies in about:studies (mozilla often offer blog posts with detailed information about their studies, which could be linked in about:studies).

Still getting this “Avast Online Security could not be verified for use in Firefox and has been disabled.” Using Firefox Browser 83.0 (32-bit)

Is that the only extension that gives you an error?

Avast updates itself frequently. I wonder whether something got broken by an update? I guess in that case there will be many more reports.

Sorry only check mail once a week.
Yes it’s the only one, not sure how long it has been a problem as I hadn’t checked in a while.

Avast and Firefox fully updated.
Avast application last update: (Ver 20.9.2437) 10th Nov 2020,
Definitions: updated today.

The info from Add-ons manager is - Avast Online Security (disabled)
Version Last Updated 2 July 2015 ?

Maybe Firefox is picking up an obsolete file from somewhere. You can find the path to the XPI file in the extensions.json file in your currently active Firefox profile. I have a page to make the info a bit easier to read (drop your extensions.json file here):

You might also check the Avast forums:

Sorry for not getting back sooner, thanks for the help.
Didn’t fully understand what I was doing with the json file, appears to have been last updated in 2019?
Tried removing and re-installing the add on which (at the moment) seems to have fixed the problem. So thanks again :slight_smile: