Calendar invitees now receive a confirmation in the browser when they accept, decline, or view an invitation from email. The change improves confidence that their response was recorded and also prevents duplicate attendee records when event partner details are updated.

…and view invitation from email

Task: https://www.odoo.com/web#id=12763&view_type=form&model=project.task&menu_id=3942&action=327

Pad: https://pad.odoo.com/p/r.eagKQBb3I0IH9dtG