Install claws-mail-vcalendar-plugin by entering the following commands in the terminal:
sudo apt update sudo apt install claws-mail-vcalendar-plugin
vCalendar message handling plugin for Claws Mail
The vCalendar plugin for Claws Mail provides vCalendar message handling (the meeting subset of the vCalendar format), displaying such mails in a nice format, letting you create and send meetings, and creating a virtual folder with the meetings you sent or received. . The functionality is similar to the one provided by Evolution for that mails.