Broken popover in local docs

Opening an issue for this after our release was delayed today.

Latest changes have broken our compiled JS files—ReferenceError: Can't find variable: _defineProperty and a couple other errors around rollupPluginBabelHelpers. These weren't present in our CI because we don't test our dist JS files. I believe @Johann-S is going to look into that so we can try our 4.1 release again soon.