When I create and send a reply for an existing message, the original message is generally marked as "replied". However, the mark doesn't appear if the original message is placed in folders having a character "," in its local file name.
Steps to reproduce
- Prepare an IMAP account.
- Create a folder with name "comma,comma" under the IMAP account.
- Put a message to the folder "comma,comma".
- Reply to the message in the folder.
The message has no mark in the thread pane.
The message has a "replied" mark in the thread pane.
- Windows 10 1809
- Thunderbird 60.7.2 (32bit) (Build ID: 20190620083217)
- Daily 69.0a1 (32bit) (Build ID 20190704092729)
This problem also appears when the folder's substance file has
, in its name as an UTF-7 encoded string. For example
&U,BTFw-. This is an the encoded version of
台北 (Taipei, a city in Taiwan)