Can't remember the name of this app

I believe the app is standalone but could be/have a web interface, too.

It aggregates popular library/language/framework API documentation on the left side, of which you can install or disable ... libraries like Lodash, Moment, Node, Express, Mocha, etc. IIRC, even JavaScript.

The app would install the documentation and you could omni-search, say, 'sort,' and the main right-side pane would collect the results.

The last I used it, years ago, it also auto-updated the documentation of each library/framework with every new library/framework release.

My web searches are in vain. Please help.