Responsive HTML 5 Output Search Issue with iPad Pro Keyboard

I have RoboHelp 2017, version 13.0.2.334.

Someone was reviewing my project online on his new iPad Pro with keyboard. He found that when using the Search feature, it would allow him to use the keyboard to type the Search criteria; however, he could not invoke the search with the Enter key (or any other key).  Searching works correctly when using the built-in electronic keyboard. I reached out to Willam van Weelden separately about this issue, and thought I would add this to the community forum in case anyone has experienced this issue.

Is there any way to resolve this issue so that users may search for topics using an iPad Pro keyboard? Appreciate your feedback.