Sorry, the Add-ons team is working on a fix for this. It looks like a certificate used to sign many popular extensions expired. (The verification process checks that certificate.)

I don't know how soon re-signed versions of those extensions will become available, or whether another workaround will be discovered. We are all hoping to learn more soon.

I have the same problem all my extensions stopped working today

Folks,

We're very sorry for the inconvenience here.

The resolution is being rolled out right now, but could take up to 6 hours to get fixed for everyone.

You can track updates to the issue through this post: https://discourse.mozilla.org/t/certificate-issue-causing-add-ons-to-be-disabled-or-fail-to-install/39047/

Sorry again, George

Mozilla has rolled-out a fix for this. The fix will be automatically applied in the background within the next few hours, you don’t need to take active steps.

In order to be able to provide this fix on short notice, they are using the Studies system. You can check if you have studies enabled

1. Go to [=] > Options > Privacy & Security.
2. Make sure Allow Firefox to install and run studies is check marked.

I you had it disabled, you can disable studies again after your add-ons have been re-enabled.

They are working on a general fix that doesn't need to rely on this and will keep you updated.

Awesome thanks for the reply guys! Looking forward to getting everything back to normal. However, one of my devices I had wiped all extentions, my main computer tho, removed all addon's/extentions automatically, w.e was in the deactive plugins page is GONE. Not by my doing but automatically which isnt not a big deal, I only use 2/3 at any given time and is just a matter of adding it back and turning on/off for specific sites. Hoping to see a fix by the end of the weekend so I can have the time to reinstall them before the rush of a new week. Will keep looking for updates until I see its fixed and we can re-download, still atm says download failed please check connection on any addon/extension so still no fix yet..

Chris Ilias said

Mozilla has rolled-out a fix for this. The fix will be automatically applied in the background within the next few hours, you don’t need to take active steps. In order to be able to provide this fix on short notice, they are using the Studies system. You can check if you have studies enabled

1. Go to [=] > Options > Privacy & Security.
2. Make sure Allow Firefox to install and run studies is check marked.

I you had it disabled, you can disable studies again after your add-ons have been re-enabled. They are working on a general fix that doesn't need to rely on this and will keep you updated.

Oh great. Was working before and now mess up for every users. That's the plan.

Correction, After having waited about 30 minutes, giving my browser a chance to connect and sync, it seems to be allowing me to reinstall my extensions/addons now. Problem here seems solved. Thanks!

Hi WestEnd, someone let a certificate expire. This happens on websites from time to time, so you just can't use that site for a few hours, but the impact in this case was bigger because there are some add-ons you use on every site. Hopefully a permanent fix will come out this week.

I'm getting sick of Mozilla disabling my extensions.These extentions were downloaded of the Mozilla website,but somehow they feel it's ok to disable extentions that they themselves provided????How do they do that anyway?Is there a back door in the browser so that they can hobble my browser at will?I am so mad that I am seriously considering Opera.I'll bet Opera doesn't pull this kind of stuff.

Please don't hand me that certificate has expired excuse either.These programs were downloaded directly off the Mozilla website.It sure seems heavy handed,and abusive to me.If the extension is not going to be supported,and yanked out from underneath you,then they shouldn't offer the extension in the first place.This has happened way to often...to the point where I really don't trust Mozilla and why I don't update my browser every time they post an update.Everytime I update,Mozilla eliminates some of my extensions,so better to just stick with older versions.

Now they are modernizing?I can hardly wait.

What happened to Firefox?They used to be THE browser to have.

Hi sierramadreme, jscher2000's post was marked as the solution by the person who asked the original question (endgame02). Your issue may have similar symptoms, but it is likely a different cause/solution. You should use https://support.mozilla.org/en-US/questions/new where volunteers can get more details about your setup.

Because this thread is solved and more people might start using it for their own questions, I'm going to lock it.