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Can work with other addon hosted sites besides just (i.e.I believe this is how the extension system was intended to work (for instance Firefox already registers itself as x-xpinstall app=firefox with the OS but that doesn't appear to be used for anything currently).Provides the best user experience for users.Thunderbird must implement a command line handler that can accept the url to the XPI we want to load and then install the extension at that url. In this case, the browser wouldn't recognize x-xpinstall app=thunderbird so we find the default handler which is Thunderbird. The addons server returns an appropriate mime type based on the application the extension in intended for. Thunderbird registers itself as a mime handler with the OS for: application/x-xpinstall app=thunderbird. Doesn't help users who want to look at extensions on other sites like extensionmirror.Doesn't help users browsing addons in Firefox or another browser from installing extensions they see and like.Clumsy user interface, too many windows.you have to log in in order to get sandboxed extensions.
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Link clicks outside of this site would get sent to your default browser.
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This window would be a single site browser which only browses through. From the Thunderbird Add-ons dialog, the "Get Extensions" link would open up a chromeless browser window that's a part of Thunderbird.
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There are currently two proposals for solving this problem:
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