Website editors can now edit LESS styling from the website HTML editor, making it easier to adjust a site's visual design without leaving the editing flow. This adds more flexibility for teams managing website appearance and reduces the need for separate technical steps.

Add LESS edition to the website "HTML" editor.
Original task here: https://www.odoo.com/web#id=8512&view_type=form&model=project.task&action=327&menu_id=4720