I tried to create a Firefox 57+ compatible add-on (i.e. a WebExtensions based add-on) containing the following code:

```js
// Import the Services module.
Components.utils.import("resource://gre/modules/Services.jsm");

var bss = Services.search; // browser search service
bss.init();
var searchEngines = bss.getVisibleEngines({});

```

only to learn that **[you can't import Services using the WebExtensions API](https://stackoverflow.com/questions/36332561/firefox-webextension-importing-services)**.

So, I'm wondering if there's an equivalent way, using the WebExtensions API, to be able to access a browser's search bar search engines (that will be compatible with Firefox 57+ and not break with Firefox 56-).