The current latest is 6.1.0, which will return malformed JSON and break things in very unexpected (to the end user) ways. If the current latest stays as-is, it's going to start breaking a lot more people come tomorrow with beginning of week.
Reverting the commit or publishing a new version is the proper/long term fix, but you'll likely get a lot more people posting issues tomorrow if they happen to pull down 6.1.0 in the meantime.