Firefox Addon will not install "Certificate issuer is not built-in"

Last Updated: 7/26/15

Problem:
If you try to install a firefox button / addon (like Pinterest) and you get a connection error message and the install does not proceed.

Solution:
Open the Firefox Menu > Developer > web console > click "clear"

try to install the addon again. go back to the web console and view the error.

find the URL fore the xpi file.

type the URL in the address bar, but be sure to use HTTP and not HTTPS.

addon should now install fine!

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