yellow highlight of index words in HTML5?

I have  a book with an extensive index which is being published as html5. The index works fine in HTML5, but I get no highlight of the chosen index words when I click them in the published output. Making it pretty cumbersome to figure out where exactly the source of the index word actually is on the page.

Is there a solution for this?

FrameMaker Version: 17.0.5.725