Visited the site in safe mode and the problem persists.
I also tried restoring the site on a different server with a Discourse install with the same app.yml, then rebaking posts, just to test if anything would change, and it didn’t.
0.22, and it’s the exact same in another forum I manage that doesn’t have this problem.
My CDN is just the basic one from Amazon AWS, and it’s with the same settings as another site that doesn’t have this problem.
Unfortunately, I don’t use any plugin that would interact with that. Maybe discourse-topic-previews-sidecar?