I’m self-hosting a minimal trello-like software I wrote https://github.com/michelematteini/tarallo… I’m using both on desktop and mobile.

That is the character set and collation that should be used, and your DB probably don’t support it. You can try by leaving the default by removing “CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci” inside init_db.sql, anywhere you find it.