It is working for me in Chrome and Edge.
There are a couple of added bits of JS functionality in the file that work in HTML5 but not flash. The 1st bit of code, finds the tab you added, moves it to the bottom of the player, and re-formats it to look like the other lower player buttons. The next code, hides the button. If you click the character, the button is revealed. If you click the text bubble, the button is hidden again.
Those extra bits aren't required, I was just teaching myself how to hack some of the html5 player elements. Really, all anyone needs to do to add the print functionality to any of their projects is the following:
1) Click Story View
2) Select Player
3) Under the Player Tabs list, click the "New" button
4) Add any name you want and choose your alignment. I typically call it "Print Window".
5) Select the action "Execute JavaScript and paste the following line of code:
window.print();