Unable to see others' chat messages / signs and written books don't work

The bug

Since 28 April 2022, my friends and I are unable to see each other's chat messages on my realm.

We tried a couple things, like changing the world, reuploading the world, restoring the world to an older back up. But nothing worked. For now we created a team, and are using /teammsg to chat with each otter. Also, /msg still works, though /say and /me are not working.

We found it out when we were just playing, I joined the game, and said hello, but didn't get any response. But they also said hello, but it didn't come to each other's chat.

Similar reports indicate that this issue may also affect the visibility of sign text to other players.