Hi, if by pure webview you mean just having the application running in Chrome or some other browser then I'm afraid this is not possible.
The recommended approach is to use Enterprise Browser for web based development, it is backwardly compatible with the rhomobile JS APIs for example the Notification API is here: Notification - Zebra Technologies TechDocs . You should be able to take your existing webview app and run it in Enterprise Browser (so EB is acting as a container for your web app). There is a license cost associated with EB.
You could still go down the Rhomobile route and that does not require a license, though Zebra no longer offers formal support or new features for Rhomobile it should still meet your needs.