The next activity done button in kanban views is now always visible on phones and tablets, instead of relying on hover behavior that mobile users cannot use. This makes completing scheduled activities easier and more reliable on touch devices.

Task: https://www.odoo.com/web#id=1838957&view_type=form&model=project.task&action=333&active_id=131&menu_id=4720

Pad: https://pad.odoo.com/p/r.8be23d8ad0ec2d0a38cea8793af6b61a