From Xojo Documentation
| This property is only available on the Windows platform.
For cross-platform compatibility, use ＃If...＃Endif with the Target... specifiers to make sure you will not attempt to use this property on an incompatible platform.
Used to specify the rendering engine used on Windows. Choices are Native (0) or WebKit (1). You can only set this property in the Inspector for the control.
The Native renderer is Internet Explorer.
Using WebKit on Windows adds the entire Chromium Embedded Framework 3 (CEF3) engine to your app, increasing its size by about 100MB.
If you need plugins when using WebKit, add them to the WebKitPlugins folder in the Libs folder for your application.
Setting this property at runtime has no effect.
When using Native, Windows uses an older version of the Internet Explorer rendering engine. You can switch to a more recent version specifically for your app with code like this: