Switched to Franz (which has gone open source) from Rambox (which has been deprecated in favour of closed source) as a container and notifier for always-open #webapps: https://meetfranz.com
Here's some useful recipes for apps not included by default:
Loomio: https://gitlab.com/mayel/franz-loomio-recipe/
Mastodon: https://github.com/sharkpp/franz-recipe-mastodon
Protonmail: https://gitlab.com/mayel/franz-recipe-protonmail