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WorkSpace: obtaining and synchronising the list of folders with a messaging software
While they are present in your Webmail it is possible that some folders don't appear in your IMAP configured email software.
In your email software, right-click on the IMAP account and find the "IMAP folders" -> "register" or "subscriptions" designation.
and for Thunderbird and other software, a search will give you some tips as a response.