Adding Focalboard to "Task management/To-do lists"

README.md

@@ -1474,6 +1474,7 @@ _See https://staticsitegenerators.net and https://www.staticgen.com_
 
 _See also [Project Management](#project-management) and [Ticketing](#ticketing)._
 
+- [Focalboard](https://www.focalboard.com/) - An open source, self-hosted alternative to Trello, Notion, and Asana. It helps define, organize, track and manage work across individuals and teams. ([Source Code](https://github.com/mattermost/focalboard), [Clients](https://www.focalboard.com/download/personal-edition/desktop/)) `Other` `Nodejs/Go`
 - [Kanbana](https://github.com/SrGMC/kanbana) - Create boards to track users and projects from flat markdown files. Forked from Crepido. `MIT` `Nodejs`
 - [Kanboard](http://kanboard.net/) - Simple and open source visual task board. ([Source Code](https://github.com/kanboard/kanboard)) `MIT` `PHP`
 - [myTinyTodo](http://www.mytinytodo.net/) - Simple way to manage your todo list in AJAX style. Uses PHP, jQuery, SQLite/MySQL. GTD compliant. ([Demo](http://www.mytinytodo.net/demo/), [Source Code](https://github.com/maxpozdeev/mytinytodo/)) `GPL-2.0` `PHP`