Upstream they have "version_added" and "version_removed" but in this package they've changed the meaning to mean "supports". I don't think that's a trivial difference unless all major browsers are going to guarantee that features never break or are never removed. I have no problem with having a boolean to tell whether the current browser supports a given feature but having the featured example be a footgun when people naturally do a simple >= isn't the best showing.
The NPM page suggests that I can query the schema object directly if I'm worried about this but the links on [1] all 404.
[1] https://www.npmjs.com/package/mdn-browser-compat-data