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WHY CAN'T I INSTALL AN UNSIGNED ADD-IN?

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Just downloaded an add-in, at the Firefox add-in site. It's an Evernote thing: evernote_tab-0.1.14-tb Anyway, it won't install - message says it's unsigned.

Why would FF allow it on their site if it isn't allowed?

Not the end of the world, just trying to get my head around how they think...

Just downloaded an add-in, at the Firefox add-in site. It's an Evernote thing: evernote_tab-0.1.14-tb Anyway, it won't install - message says it's unsigned. Why would FF allow it on their site if it isn't allowed? Not the end of the world, just trying to get my head around how they think...

Chosen solution

Starting with Firefox version 48, the add-on signing requirement will be enforced with no override in Release and Beta versions of Firefox. See the MozillaWiki article; https://wiki.mozilla.org/Add-ons/Extension_Signing for more information.


This will disable add-on signature enforcement; Firefox ESR version only. Enter about:config into your Firefox address bar Click the I'll be careful button Find xpinstall.signatures.required in the list Right click the preference Select Toggle until the value is false https://support.mozilla.org/en-US/kb/add-on-signing-in-firefox


You can install the Firefox ESR 52 version which will get security updates into early 2018, to get "more time" using Firefox.

Firefox; Extended Support Release {web link} ESR Notes System Requirements

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All Replies (7)

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I think this extension -- for Thunderbird, not Firefox -- is obsolete due to age and version incompatibility, and may not have been signed for that reason.

https://addons.mozilla.org/thunderbird/addon/evernote-tab/

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Chosen Solution

Starting with Firefox version 48, the add-on signing requirement will be enforced with no override in Release and Beta versions of Firefox. See the MozillaWiki article; https://wiki.mozilla.org/Add-ons/Extension_Signing for more information.


This will disable add-on signature enforcement; Firefox ESR version only. Enter about:config into your Firefox address bar Click the I'll be careful button Find xpinstall.signatures.required in the list Right click the preference Select Toggle until the value is false https://support.mozilla.org/en-US/kb/add-on-signing-in-firefox


You can install the Firefox ESR 52 version which will get security updates into early 2018, to get "more time" using Firefox.

Firefox; Extended Support Release {web link} ESR Notes System Requirements

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Thanks to both of you for the quick replies. Just started using FF, and this was my first post. As I said, the add-on wasn't important to me, but I was curious as to why FF would post an add-on they say it's not allowed. Gonna skip the add-on, but appreciate the information provided by both of you.

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There are many add-ons available. Another may be able to do what you want.

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I have an old addon that FireFox has disabled. Is there no way to enable it without using a different (eg ESR) Firefox version?

Thanks.

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FredMcD said

Starting with Firefox version 48, the add-on signing requirement will be enforced with no override in Release and Beta versions of Firefox. See the MozillaWiki article; https://wiki.mozilla.org/Add-ons/Extension_Signing for more information.
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Hi skywalka, if you look at the detailed explanation, is it because it "could not be verified" or for some other reason? "Could not be verified" indicates that it does not have the currently required digital signature; more info in other posts. But there may be other reasons.

To check the explanation, go to the Add-ons page. Either:

  • Ctrl+Shift+a (Mac: Command+Shift+a)
  • "3-bar" menu button (or Tools menu) > Add-ons
  • type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions. Then find the disabled extension on the right side (usually at the bottom of the list) and click its "More" link. The detailed explanation should be at the top of that page.