Notion does allow iframe
ClickUp works very very well in the iFrame.
Allows you to ‘login’ and access all private boards as required.
ClickUp is project management & task management on steroids.
Thanks for this tip; just what I needed!
Miro seems to embed fine, but the login is not working for me, so I can only see public boards (and not work on my boards either)
Monday.com also embeds fine, but no login option there