This is the chart of the votes for the latest posts on !apocalypticart@feddit.de.
This may be just a coincidence, but I find a bit weird that the votes went down to almost zero exactly when lemm.ee[^1] and feddit.de[^2] upgraded to v0.19.
[^1]: the instance from where I'm posting [^2]: the community instance
We were just discussing some potentially-0.19.1-related federation problem that lemmy.today users were experiencing after the update; that's how I ran across this thread.
https://lemmy.today/post/4382768
The admin there, @mrmanager@lemmy.today, restarted the instance again some hours later to attempt to resolve the problem, and it looked like federation started working at that point.
That might be worth consideration if any other instances are seeing problems with posts/comments/votes not propagating.
EDIT: Well, nuts. Now this comment doesn't seem to be propagating either; visible from lemmy.today but not on lemmy.ml's Web UI. Maybe if lemmy.today gets restarted again, it will.
Posting from a kbin.social account to avoid the lemmy.today issues -- on lemmy.today, the current behavior looks like the messages in the queue go out when the instance is restarted, but not until then. It's running 0.19.1.
I am not the admin there, but wanted to make that available in case other instances are affected and trying to diagnose similar behavior; federation problems themselves can cause communication problems in trying to understand the issue.