The sent folder is not visible
The sent folder is not visible but I still can click on the line and the message still can be read in the message pane. But, the message cannot be open if I double click on the message.
Wšě wotmołwy (2)
Why no reply, please help!!
You posted in the Firefox support fora queue. Firefox doesn't do email, it's strictly a web browser.
If you are using Firefox to access your mail, you are using "web-mail" such as Yahoo!Mail or Gmail. You need to seek support from your service provider or a forum for that service.
https://support.mozilla.org/en-US/kb/problems-with-email-how-to-find-help