Which engine am I using?
Check the source code, look for an “EngineToUse” statement

If running .NET it will look this
oWG.EngineToUse = APWebGrabberInterface.ConversionEngine.Native;

If deployed in COM, you’ll see this
' Rendering engine used for the HTML
' 0 = Native, 1 = IE
oWG.EngineToUse = 0.

If the EngineToUse is not explicitly stated in the code, then it is defined in the Configuration manager.
Note that the source code overrides the Configuration Manager, so check the source code first.

If you are using WebGrabber from 2013 R1.0 to 2016 R2.0 with the native engine and the EngineToUse property is not explicitly stated in the code then no action is necessary.