Install claws-mail-attach-warner by entering the following commands in the terminal:
sudo apt update sudo apt install claws-mail-attach-warner
Description:
Missing attachment warnings for Claws Mail
This plugin for Claws Mail warns the user with a popup window if some reference to an attachment is found in the composed mail text but no file is attached.
Homepage: http://www.claws-mail.org
Version: 3.16.0-1
Section: universe/mail