Thunderbird add-ons corrupt or unverified

I was trying to install some thunderbird add-ons from addons.thunderbird.net/en-GB/thunderbird/ and I noticed that a number of them cannot be installed because they are either corrupt or unverified. Here are some examples, all taken from the featured add-ons (but all other add-ons I tried suffered from the same issue).

  • Enigmail: unverified
  • Mail Merge: corrupt
  • Compact Header: corrupt
  • Mail Redirect: corrupt
  • Card Book: corrupt

My Firefox is up-to-date at 61.0.1 (64-bit), and I have disabled all my add-ons (just in case). Is it something on my end or is this a problem with the site?

See this post.

https://support.mozilla.org/en-US/kb/thunderbird-add-ons-frequently-asked-questions#w_installing-add-ons-downloaded-from-outside-thunderbird-e-g-using-a-web-browser-like-firefox

Sure: installing from “Extensions” withing Thunderbird works. But trying to install from “Get Add-ons” within Thunderbird opens the webpage above, and clicking on any of the “Download Now” green buttons triggers Firefox to install the add-on, which results in an error message. This clearly isn’t be the intended behaviour, so there is something to be fixed here.

Thunderbird 52.9.1 did not get an update to point to addons.thunderbird.net and still looks for addons.mozilla.org.

  I suspect that won't be fixed because Thunderbird 60.0 should be released soon, where using Tools > Add-ons > Get Add-ons works as expected because it opens addons.thunderbird.net in a new tab within Thunderbird.

Does the behavior deviate from what is described at https://support.mozilla.org/en-US/kb/installing-addon-thunderbird ?

Using TB 52.9.1 the behavior does not deviate from the Ideal Case. Search for an extension and a list of results open in a new tab in Thunderbird.

If the user selects the Get Add-ons panel and tries to install an extension by selecting a Featured Add-on, the add-on opens in Firefox with the link,

https://services.addons.thunderbird.net/en-US/thunderbird/discovery/addon/silvermel/?src=discovery-featured

Using Thunderbird 60 rc, any extension selected in the Get Add-ons panel would open in the Add-ons Manager tab in Thunderbird ready for installation.