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
Either 19.1 or rc.1 fixes the bug from what I saw.
But the question then becomes when the last post was made to apocalyptic art. From my quick glance it was 4 days ago on the lemmy.ml mirror, which seems behind the most recent posts on the actual community. Lemmy.ml is on the newest version.
So my guess is that there’s some general federation issue, possibly on the feddit.de end, which is causing some things to get dropped.
If that’s not the issue, then there could be a similar bug that hasn’t yet been noticed.
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.
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.