So I recently released my private addon to my team. It’s set to invisible so no one who doesn’t have the URL can download it, however, when I told them to try the Mozilla version they were met by this page:
A private addon means you need to distribute it yourself. The url inside AMO to your addon file will not be publicly available.
When you choose to distribute an add-on yourself, it can be installed to your team using the following methods:
Web download—make your extension available on a suitable web accessible server and when the user downloads the signed add-on file Firefox will install it.
Sideloading add-ons—enables a user to install an add-on using an XPI file saved on their computer.
Add-ons for use with a desktop app—this section describes the best practices for delivering an extension for use with a desktop application.
Add-ons in an enterprise environment—this page discusses the use of signed compared to unsigned extensions, installation options, the Firefox settings affecting installation, and including add-ons with a custom Firefox install package.