Rated 3 out of 5 stars

le andrybak ar Feabh. 4, 2023 ·

The addon only wraps the lines visually. The actual outgoing emails will still have very long lines, which is not good for plain text mailing lists.

Léirmheas ar leagan níos sine den bhreiseán seo (1.4.1). 

le Jan Kiszka (Forbróir) ar Feabh. 4, 2023 ·

Did you "make sure that "mailnews.send_plaintext_flowed" is disabled" (see add-on description)? If so, please share more details about your setup.
Your use case is also my use case and the primary reason why I'm maintaining this.