Javascript warning and Add Media button broken while WP Help installed

After installing WP Help I have had an unresponsive browser and the Add Media button not working (specifically for editing WP Help posts).

In my web tools console the following warning shows up:

mutating the Prototype of an object will cause your code to run very slowly; instead create the object with the correct initial Prototype value using Object.create

And the script it flags up is https://widgets.wp.com/notifications/build.min.js?etc…

I’ve tried disabling all plugins apart from WP Help and the issue remains. Also deactivating WP Help doesn’t fix it either, I have to remove it completely to get things working normally again.