WKWebView vs UIWebView

mapbox-gl-js version:

Question

Currently using MapboxGL (0.50.0) within a Cordova (8.1.2) app ( I understand that using the iOS SDK is probably the best option, but due to time constraints and limited resources, we're trying to get one codebase to work across multiple environments for now ). The current iOS platform version is 4.5.5.

Will start by saying that MapboxGL is working spectacularly in browser, and Android. It had also been working great in UIWebView on iOS.

Unfortunately, after getting off of UIWebView in favor of WKWebView, the map loads but does not include any of the styles/details/terrain/etc. IE: The continents are rendered but no relevant information shows.

Note: We're not using any fancy/custom styles. Have tried the basic template, and streets/v10.

The app is loaded via file:// ... I know there are some known issues with XHR requests in WKWebView (as a result I am using https://github.com/oracle/cordova-plugin-wkwebview-file-xhr ). I'm not sure if there's something going on there that is preventing the style URL from being fetched. With that being said, I even tried hard-coding the style JSON directly into the mapbox initialization ie:

    this.map = new mapboxgl.Map({
      container: this.mapIdentifier,
      style: {...MASSIVE JSON BLOB ...},
    });

... but saw the exact same results.

If anyone on your team has seen this kind of problem or is aware of any issues between mapbox-gl and iOS WKWebView, I'd greatly appreciate any advice.

Thank you!

Links to related documentation

No repository file or test is named. Start by reproducing the mapbox-gl 0.50.0 behavior in the stated Cordova 8.1.2, iOS 4.5.5 WKWebView setup, comparing file:// loading with the hard-coded style JSON; done means identifying the cause and documenting or verifying a focused fix.