Have the option to toggle on and off the purple text in the Reader App

The pilots have asked if we can have the function to toggle off and on the purple text in the Reader app once they have read and acknowledged any changes in a document.

At the moment Admin can switch it on and off but that affects all areas.

Would anyone else be interested in this as a development, so that the pilots have the ability to turn it on and off in the app on their personal iPads? 

Thanks