Thunderbird 3.1.7 on Windows XP
With Inbox selected, when I click on a message subject in the top right pane (message list), "Loading Message" flashes up in the status bar. For some messages, especially those with attachments, there is a 4 second wait after I click on the message subject, then the "Loading Message" status. For large attachments there is another wait at that point, presumably while the attachment is downloaded (again) from the server.
Under Junk Settings, I do NOT have "Enable adaptive junk mail..." checked.
Under Server Settings, I do NOT have "Fetch Headers only" checked.
I want Thunderbird to download each message & attachment ONCE.
When I click on the subject in the message list, I expect to see the message text immediately.
In the related question, the writer had this same problem 4 years ago, and it magically went away.
Has anyone figured out that magic?