Spacedeck, a web based, real time, collaborative whiteboard application with rich media support

[jdaviescoates]

See:
https://github.com/spacedeck/spacedeck-open

It's used in the new Nextcloud Whiteboard included in Nextcloud 21 which is out today:

https://apps.nextcloud.com/apps/integration_whiteboard
https://github.com/eneiluj/integration_whiteboard

But I guess it'd be nice to be able to use without using Nextcloud too.