Just the last one, right before the EOF.

Speaking of EOF, I wonder what a heredoc might do with this 😇

Not if you choose to replace the correct ones at the correct place and it is a compiler which automatically ignores this wrong semicolon.

You could connect two lines, which may still "work" if not split using a semicolon and are then interpreted as one single line.

You are right .. but, you're not thinking big enough.

Think .. sticky tape on the bottom of a mouse.

would you say openRC or rc-service returns better or more helpful error messages with these kinds of things?

I think most daemons would log a helpful enough error message regarding incorrect syntax e.g. if it's a config file of variable=value; format then it wouldn't expect two equals signs on the same line.