I had a similar problem (posts containing custom emojis weren’t marked for rebake during the migration to S3 if there were no other uploads in the raw post, and therefore the cooked link didn’t point to CDN).
I fixed it by deleting and reuploading just one of the custom emojis, and this automatically triggered a task which rebuilt all posts with custom emojis (but I’m sure there is also a rake task which can be used to rebake posts with custom emojis directly).
I see the problem in admin/customize/emojis as well as in the post editor preview as well as retort reactions on posts done in the past hour fail.
So this doesn’t just affect old posts that use emoji, but also new posts and parts of the UI (the retort reaction picker also uses the wrong URL like the admin emoji management area).
So it does. If I actually post, the emoji is shown correctly in it.
If the fix for the retort plugin is similar to how the admin area would be fixed, I could maybe give it a shot trying to fix the plugin as the custom reaction emojis are quite widely used on my discourse instance.
I tried fixing this myself after having a quick look.
So by fixing that, it would probably fix all of the problems, right?
After that quick look I found a place that seems to build the URLs for the custom emojis and I changed that to this:
I tested with rails console and that seems to fix the URLs on my production site. So I tried deploying that change there, however it didn’t work.
After that not working I also tried to change the EMOJI_VERSION to 10 to try to get something updating, but that didn’t work either. When I do launcher enter and git log I see my commit there. I followed the approach here: