npmhub is a browser extension that lets you explore npm dependencies on GitHub and GitLab repos. When viewing a repository's file list containing a
package.json, this extension will display links and descriptions for each dependency at the bottom of the page.
GitHub Enterprise, GitLab Enterprise and Community Edition are also supported by right-clicking on npmhub's icon in the toolbar and selecting Enable npmhub on this domain.
The Chrome version also works in Opera (using this) and Edge.
Here's what npmhub looks like: