Install libclaws-mail-dev by entering the following commands in the terminal:
sudo apt update sudo apt install libclaws-mail-dev
Description:
Development files for Claws Mail plugins
This package provides the development headers needed to build plugins for Claws Mail client. Plugins are loadable modules which extend Claws Mail capabilities.
Homepage: http://www.claws-mail.org
Version: 3.16.0-1
Section: universe/devel