Merely _defining_ a custom search with this addon is trivial.

But nothing in any bit of documentation I've been able to lay hands on tells me how to do any of the following:

* Add this custom search to Firefox' list of default searches.
* Replace ordinary Firefox search with my just-defined custom search in the search window.
* Use the newly defined custom search in any practical way whatsoever.

The newly defined custom search simply vanishes. Without a referent or any practial means of actually sending it the search query I type into the search bar.

The icon shows up nowhere. The name of the custom search shows up nowhere.

The documentation on github leads me down a blind alley.

This addon does not appear to have any practical use.

Doesn't work with FF 74.