I tried to use the /trigger command inside the clickEvent of a sign.
-> The player without any op-permissions can click the sign to execute the command.
-> The player needs to have op-permissions to execute this command by clicking on the sign even though it is a command that usually doesn't require any permissions.
Since executing these commands via klicking on a JSON text in a tellraw or a book works I expected it to work in signs as well.
- I made sure to constantly enable the trigger objective via a ticked function
- I tested other non-op commands like /me and they also don't work in signs