Notes window disappears if moved too quickly.
Moved from https://www.froihofer.net/bugzilla/show_bug.cgi?id=56
This was introduced by some Thunderbird version < 35 and I assume it to be a bug in Thunderbird's dialogue movement handling. If this happens, the note's position can be reset to the default location using the context menu in the message list.
Bug still exists as of January 3, 2021. One workaround is to move it slowly.
TB 91.13.1, win 10 I just installed it, v3.3.2. For 2 emails the Notes Window has now completely disappeared and cannot be restored by reset with "note's position can be reset to the default location using the context menu in the message list". Also no edit is possible anymore. In the eMail itself the notes are still there. TB restart does not help either.