If you convert a world from at least 14w32d (most likely other snapshots too), special characters will become into unicode format on signs, and with "'s at the start and end of lines.
If you convert a world from at least 14w32d (most likely other snapshots too), special characters will become into unicode format on signs, and with "'s at the start and end of lines.
Do not downgrade worlds. Older version can't know what happens in newer versions.