Full screen in entire scene

Hello,

In my project I make use of screenshots and screen recordings of a system which we explain with a Storyline course. The thing is that the text on these screenshots is quite small, but we can't enlarge the font size or zoom in on part of the screen. I tried to see if there was an option to see the full course in full screen, but so far I only found Javascript codes that you need to enable for every slide. This results in the user clicking on a button 'full size' in every single slide. 

Is there an option to click on the button 'full size' just once, so it will be active in the entire scene?