Please try to comment and post things now, and see if they federate again.
Hopefully you see your activity instantly federated. I have tried making comments both to instances running Lemmy 0.19.1 and 0.18.5 and they all federate like they should.
Hope you have the same experience! 🥳
They should be there now - it seems a restart of Lemmy is still required for posts to federate…
For me Lemmy was working very well yesterday though, and I got responses to posts and comments right away. However, it seems like federation stops to work after a while again. The site I linked before:
https://phiresky.github.io/lemmy-federation-state/site?domain=lemmy.today
That one was showing that we had thousands of lagging instances and no updated ones just a few moments ago. And after a restart, they are all up to date again. So absolutely some bug remaining…