As you may know Claris switched the engine for WebViewer on Windows. Instead of Internet Explorer they now use the WebView2 component from Microsoft for FileMaker 19.3. Sadly we didn't get our plugin to work with this Edge/Chromium engine for FileMaker 19.3.
But we like to let you know that we work on a fix with Claris. With a little help from them, the plugin can actually get the reference to the WebViewer. For a future plugin version we can get our WebView functions to work with WebView2. But this change on Claris' side requires an update to FileMaker Pro, so this won't work for FileMaker 19.3, but for the next version after this, let's name it 19.4.
We look forward to the fall with a new FileMaker Pro release for Windows to have you all try the new functions.
Be aware that the Chromium/Edge as engine may behave a little bit different, so you need to test all scripts. And we may have a few new functions for WebView2 specific. Since WebView2 component gets regularly updated, you may need to have a recent version installed to use all plugin functions as some require a recent version, e.g. one from 2021 instead of the one from 2020.
If you like to try it soon, you may want to join Claris ETS (external testing service) and get early access to future FileMaker versions. Otherwise wait for the release, probably in fall 2021.