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The Config Editor is accessed via Preferences > Prefernces Preferences > Advanced -> General > Config Editor.

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Depending on the setting of TBC, folders on the server that the client has Thunderbird is not subscribed to are invisible or shown greyed out.

To subscribe to folders, right click any folder and choose Subscribe.  Expand the list until the folders you want to subscribe are visible, toggle (\?) the checkbox and click Subscribe.

After IMAP changes (including a cyrus reconstruct that fixed something), right click the account and choose "Subscribe ...".

Usage

Archive folder removal

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Sample script to be run in the desktop environment (TODO: $LOGNAME does not have a value ...?  The ; after imap:5 is spurious ... ?):

#!/bin/bash
export NSPR_LOG_MODULES=imap:5;
export NSPR_LOG_FILE=/tmp/$LOGNAMEthunderbird.imap.$(date Y-%m-%d@%H:%M:%S).log
/usr/lib/thunderbird/thunderbird &

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