#5 Poor Performance When Closing Very Large Messages

[Mark]

If the currently displayed message is very large (ie,
several megabytes - use "Join Messages" with a few
binary messages to create an example), there is a pause
when closing the window, or moving to another message.
During this time, the memory drops further by a few
megabytes, before all the memory is freed.

The problem is the call to TextEditor's
MUIM_TextEditor_ClearText.

It is possibly worth contacting the texteditor author on
this - in particular, the pause when clearing the text
seems a lot longer compared with reading in the text, so I
don't know if this is for a good reason.

However, we really shouldn't be displaying binary parts in
the text editor, so a suggested fix is to not insert
uuencoded/yencoded files that are embedded in the
message (possibly provided a menu option to display
these hidden sections, just in case we get a false
detection?)