Symptoms
- The web page doesn't render or work correctly.
- You're experiencing the issue with 3D WebView for UWP / Hololens.
Cause
Either the InternetClient UWP capability isn't enabled or the web page doesn't support the EdgeHTML browser engine.
Resolution
If the web page is completely blank / white, then then first step is to verify that the InternetClient capability is included in "Player Settings" -> "Publishing Settings" like described on the Getting Started page. If you add that capability after you've already generated a build, then please delete the existing build folder (instead of appending to it) in order to make Unity regenerate the app manifest with the correct capabilities.
If #1 doesn't resolve the issue or if the page renders partially but doesn't work correctly, then it may be that the web page uses a feature that isn't supported by the EdgeHTML browser engine. 3D WebView for UWP is powered by the UWP WebView component, which uses the EdgeHTML browser engine (v18). EdgeHTML is the browser engine that was previously used by Edge browser until it switched to Chromium in 2020. EdgeHTML doesn't support some of the newest JavaScript and browser features, so if a website isn't rendering or working correctly, it may be because it uses a feature that isn't supported by EdgeHTML. To check if that's the case, please test with a legacy version of the Edge browser using the steps described here.
Note: new versions of the Edge browser app (including on Hololens) don't exhibit this issue because the Edge browser app now uses Chromium as its browser engine instead of EdgeHTML.