Browse to the location where the TorBirdy XPI (get it from [https://addons.mozilla.org/thunderbird/downloads/file/199062/ Mozilla Add-ons]) is saved and then select it. Click ''Open''.
Browse to the location where the TorBirdy XPI (get it from [Mozilla Add-ons](https://addons.mozilla.org/thunderbird/downloads/file/199062/)) is saved and then select it. Click _Open_.