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Description
One problem we're going to be facing, now that I'm thinking about it:
We will be introducing the ability to specify a custom output format with #582.
This new output support (the env-var support) won't be available for older versions, which means debug will now be showing different output formats for old versions of the library, which is a problem since debug is almost as old as node.js IIRC.
That means users that set DEBUG_FORMAT will see inconsistent output formats for code that is any older than the new major version release.
Should there be a compatibility layer introduced in the newest version that sniffs out older versions of debug and patches them up, being version-aware in terms of the API?