I flag messages to add them to the agenda. When the todo is finished, I “unflag” the message (in the message list or in the agenda) and it vanishes from the agenda. So far so good. If I move the message to the “all messages” folder to archive it, it always becomes flagged again and reappears in the sidebar. So I need to first archive it and then remove the flag in the sidebar to make the flag vanish for good.
This is really becoming disturbing! Sometimes I have to remove the flag 3 times to have it gone for good. I remove the flag (from sidebar or maillist) and archive the mail: the flagged mail reappears in the sidebar. I remove the flag from the sidebar. Then someone answers in the same conversation, already deflagged twice: it of course should reappear in the inbox, but it reappears flagged once more!! If I remove a flag I want it gone for good. Every time. Flagging is by concept purely manually controlled.
I mostly flag ToDos. When the ToDo is done, the flag should go. I reply to the person to say: its done. In the conversation, archived, the person often replies with a plain “thank you”. That is NOT important and should not automatically get re-flagged 