Get WebView implementation programmatically

It is of course possible for a user to choose which WebView implementation to use, as explained here. Is it possible to determine programatically which implementation they have chosen? I know that it's possible to get the User-Agent string programatically, but that's not quite the same information.

In the above example, I want to know that "Chrome Stable" has been selected as the WebView implementation. On some user devices, there is apparently also an option to choose "Android System WebView" from the list, even though Chrome is also an option, and even though the Android System WebView is disabled in the system apps listing.

This is troubling because presumably the Android System WebView will be receiving no further updates (it will be stuck in the past), while Chrome will be receiving updates and is the more appropriate choice as the WebView implementation. It is even more troubling because the selection of WebView implementation is completely hidden from the ordinary user.

So I want to know particularly if "Android System WebView" is selected, even for Android 7.0+ where it would seem more appropriate that Chrome is selected instead.