Recently I've tried to make posts & comments to a couple remote instances (slrpnk.net & just now sh.itjust.works), and while they appear to post correctly (not getting stuck on spinning create/submit circle), they never appear on the remote instance.
In the case of posting to slrpnk.net I gave it a couple days before posting this, as I know sometimes federation can be finicky (and it's hard to tell whether it's your end or their end). With sh.itjust.works, I admittedly haven't given it much time yet (only just posted), but from experience I know typically the delay isn't that long unless something may be going awry.
Still, I thought it worth reporting, as I suspect some may not have realized it just yet as they're still getting used to things around here & may only be posting to local Lemmy.World communities.
Edit: I did another test just now with a comment over on a lemmy.one thread which did federate promptly (albeit the edit's taking its time carrying over), so now I'm really not sure what may be going on here.
Of the three, I'd think slrpnk.net should have the fewest delays, being a smaller instance, whereas I understand the delay with sh.itjustworks, but then I see that it appears it may have roughly a similar amount of folks to lemmy.one...So, yeah. Situation's unclear.
I've also noticed this issue. Some of the some posts and comments I and others have been making on a dormi.zone community haven't been going through to the remote instance, but others have been. No noticeable rhyme or reason for which get through and which don't.
I can confirm. It's really strange. There are posts hosted on lemmy.ml, where the comment section - when viewed from lemm.world - is 10 time larger then when viewed from lemmy.ml. Sometimes lemmy.world users are having complete conversations nobody from another instance can see.
Its the same comment section hosted my lemmy.ml, but when viewed via lemmy.world/c/[email protected], much more comments show up, the extra comments are only visible to lemmy.world users.
And it's not limited to lemmy.ml. I saw the same thing happening on post hosted by feddit.de.
It's normal that there is a delay between posting a comment & and it appearing on other instances, since federation happens in a separate queue. But I wonder if lemmy.world has simply become so big that sometimes the queue worker(s) can't keep up anymore and then it takes forever for comments to get through.