*: web_editor, portal This adds a button to add language in theme tab. When clicked, opens the "add a language" wizard. If the website has only one language, the options to enable language in header & footer are hidden. When an user add a language, the default behavior is Header: dropdown & Footer: inline. Also provides two more rendering options : Language Code and Flag + Language Code. task-3457554 closes odoo/odoo#119650 Related: odoo/design-themes#651 Related: odoo/upgrade#5214 Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com> Co-authored-by: qsm-odoo <qsm@odoo.com>