Bug: Any POP account folder changes behavoir to draft folder type when new message is saved after selecting "Options" -> "Save Copy in Folder" (NOT being THE draft folder)
Status: UNCONFIRMED
Priority: --
Created: 2023-07-05 15:21:14+00:00
Resolved: 2024-04-27 13:15:15+00:00

Steps to reproduce:

Using nested folders in a POP account to organize mails. Using Thunderbird's standard odering for those folders. Folder names are chosen to influence the order as desired.

Some folders are special folders, such as Inbox, Draft, Sent, Trash, Junk; all of them show an idividual icon. None of them can be deleted. All of them are show at the tops of the folder list.

When creating and sending mails from that POP account, I usually do "Options" -> "Save copy in... (folder)", then select one of my own (sub)folders to have a copy save in that folder upon "Send". This basically works as desired. 

However, there is an unwanted behavoir when the new message is *saved before sending it*, either manually ("File" -> "Save"), automatically (when "auto save interval" has elapsed): Thunderbird changes the folder from type "user" folder to type "draft" folder, internally. The unwanted consequences of this are:

1. Folder's icon is changed from standard folde icon, to special folder "Draft" icon.
2. Folder is sorted at top of the list of folders, or at the top of the list of subfolders.
3. Folder can no longer be renamed.
4. Folder can no longer be deleted. 
5. The message saved is the unsent version; it is missing all the "sending" information (returned from the SMPT server). If opened, it shows irritating message "No identity was found that matches the email address in the from field...".


Steps to reproduce:

a) Create a POP Account
b) Create a user folder, say "Draft Testing Main"
c) Create three subfolders in that folder, say "10 - Draft testing Sub 10", "20 - Draft testing Sub 20", and "30 - Draft testing Sub 30"

With TB standard odering, the folders are shown as:
...
Junk (junk folder icon)
Trash (trash folder icon)
Draft Testing Main (standard folder icon)
  10 - Draft testing Sub 10 (standard folder icon)
  20 - Draft testing Sub 20 (standard folder icon)
  30 - Draft testing Sub 30 (standard folder icon)
any next folders....

d) create new message, fill in required fields, and body, select "Options" -> "Save copy in ... (folder)" -> "10 - Draft testing Sub 10", then immediately hit "Send".

The message is sent, *and* a copy is save in the selected folder (and another copy is saved in the standard "Sent" folder).

e) Create another new message, fill in required fields, and body, select "Options" -> "Save copy in ... (folder)" -> "20 - Draft testing Sub 20", then *don't* send now. Either await the "autosave interval" to expire, or manually do "File" -> "Save". Only now "Send the message".

TB is saving an unsent message, and because of this, it is changing the folder type from "user" folder to (internally recognized) "draft" folder. Consequences describe above.

With TB standard odering, the folders are shown as:
...
Junk (junk folder icon)
Trash (trash folder icon)
Draft Testing Main (standard folder icon)
  20 - Draft testing Sub 20 (DRAFT folder icon)    <<====
  10 - Draft testing Sub 10 (standard folder icon)
  30 - Draft testing Sub 30 (standard folder icon)
any next folders....




Actual results:

Thunderbird changes the folder from type "user" folder to type "draft" folder, internally. The unwanted consequences of this are:

1. Folder's icon is changed from standard folde icon, to special folder "Draft" icon.
2. Folder is sorted at top of the list of folders, or at the top of the list of subfolders.
3. Folder can no longer be renamed.
4. Folder can no longer be deleted. 
5. The message saved is the unsent version; it is missing all the "sending" information (returned from the SMPT server). If opened, it shows irritating message "No identity was found that matches the email address in the from field...".


Expected results:

TB shold not change the type of folder, and leave it as a plain "user" type folder.