Nope this is still behaving strangely.
I have seen a warning in the log about the emoji plugin not being compatible!
Emojis present on first page load as broken images, a page refresh displays them. Navigate away and navigate back and they are broken again.
The Build Emoji button has always completed successfully in my experience.
Sometimes I try then also a full rebuild via the ACP. None of this seems to make a difference.
Finally, I tried to create a custom emoji, while it saved, I had to buy;/restart to get it to appear int he selector panel.
Tried a custom emoji, same deal, it appears as a broken image, refresh's and it's there. Nav away and back to page, all broken again.
Maybe there is something at the nginx level that needs to be addressed.