Embedded indexing option no longer working on DC version

[defaultnodqns9tpss9]

Enabling embedded indexing in the registry editor used to be sufficient when searching large pdf documents without requiring the tool in the pro version to create a registry 

This no longer seems to work after recent updates. has something changed?

I'm working with 50k page documents and a simple search takes a VERY long time 

https://helpx.adobe.com/uk/acrobat/kb/enable-embedded-index-to-search-pdf.html 

[defaultnodqns9tpss9]

Edit: *without requiring the pro version to create an Index 

[Test Screen Name]

"With December 2018 release of Acrobat DC and Acrobat Reader DC, the embedded index in the PDF is no longer used for searching." (and here's how to make it work again)

https://helpx.adobe.com/acrobat/kb/enable-embedded-index-to-search-pdf.html