Between those screens I used ctrl+e (navigate). My word wrap is not to print margin (as you can see). With print margin there is no problem.
My screen resolution is 1680px wide but I squeeze in two windows horizontally so Cloud9 sits at 840px. Those left hand panes (workspace etc.) take a big chunk of the window when opened which causes the editor to have only 400px or so and the text gets squished and just never returns to normal.
I use Opera 39.0 because it lets you disable browser keybindings to avoid crashing horribly with Cloud9 bindings.