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Why was Lightning installed through official Firefox Add-ons said to be unsigned.

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  • 2 have this problem
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  • Last reply by Armadillo

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When I went to the official Firefox Add-On site (https://addons.mozilla.org/en-US/seamonkey/addon/lightning/) & tried to install Lightning in Firefox 49.01.1 I received a message that Firefox has prevented this site from installing an unverified Add-on. Following up on this, I understood that Firefox would not allow an unverified or unsigned Add-on from being published on the official site.

When I went to the official Firefox Add-On site (https://addons.mozilla.org/en-US/seamonkey/addon/lightning/) & tried to install Lightning in Firefox 49.01.1 I received a message that Firefox has prevented this site from installing an unverified Add-on. Following up on this, I understood that Firefox would not allow an unverified or unsigned Add-on from being published on the official site.

Chosen solution

As the description says Lightning is only for Thunderbird and SeaMonkey (as it has a email client built in suite) as it is a Calendar.

https://addons.mozilla.org/seamonkey/addon/lightning/versions/ Works with SeaMonkey 2.42 - 2.42.*, Thunderbird 45.0 - 45.*

The section for desktop Firefox is at https://addons.mozilla.org/firefox/ as you were in SeaMonkey section.

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All Replies (3)

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Chosen Solution

As the description says Lightning is only for Thunderbird and SeaMonkey (as it has a email client built in suite) as it is a Calendar.

https://addons.mozilla.org/seamonkey/addon/lightning/versions/ Works with SeaMonkey 2.42 - 2.42.*, Thunderbird 45.0 - 45.*

The section for desktop Firefox is at https://addons.mozilla.org/firefox/ as you were in SeaMonkey section.

Modified by James

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I understand. Thank you. I started out at the desktop Firefox section, but when I searched for Lightning, as I was interested in a calendar, I was sent to the SeaMonkey section, and didn't realize the change. Looking at Thunderbird Email, am I correct that it is still in Beta?

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I am one of the few internet users who have elected to use Thunderbird and Firefox as independent applications. Something went terribly wrong in SeaMonkey development and I had ti leave it behind after decades of following Netscape. The question I have, and cannot find an answer is as follows: Is there a way to invoke the Lightning Calendar from FireFox when both applications are installed and Lightning is a plugin for ThunderBird?