User blog comment:RottenBlock/System Programming Resources/@comment-40164738-20200302113330/@comment-31720212-20200303002722

Ah, good, it was just the ZH command, then? Good to hear.

Yes, if the program doesn't ever use ZH 0, you can throw ZH 1 in at the start of the game and be done with it. Short of loading files created when ZH was still 0, you won't see full-width characters again!