I want to enrich a web application with accessible keyboard shortcuts based on simple data-attributes. In the best case I'd like to include a standalone javascript library that does all the magic including a generated help-popup that can be accessed by CMD+? oder STRG+? respectively.

For example like this:

<button data-accesskey="cmd+f" title="Start a search">Search</button>

By pressing CMD+? the user shall be presented a centered overlay on the page that lists all defined accesskeys and their description (title or a 2nd data-attribute).

Before going all in and creating such implementation myself I wanted to check back if there already is something like this.