email - Thunderbird 3: see size of folder?

In Thunderbird 3, how do you see the size of a folder? I.e. the total size of all emails in a certain folder?

Answer

ShowFolderSize 0.2 is an extension that shows in the status bar and in the properties window the filesize on disk of the folder. The label in the status bar becomes red when the size folder exceeds the limit.

Tested with TB3 in Windows:

Download the XPI file and install via Thunderbird Addon Manager.

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