Are you in Canada? It was reported that the keyboard of the model sold in Canada has "international characters", has a shorter left shift key and a non standard return key. My guess is that the layout is the CAN/CSA Z243.200-92 standard, a.k.a. "Canada Multilingual" keyboard layout.
I got my One. I was wrong, the keyboard layout isn't "Canadian Multilingual".
Just to be clearer: the green characters represents the keyboard layout "French Canadian", to be used by French Canadians. The green characters replace the black characters when the French Canadian keyboard layout is used, but before that it must be configured in Linpus Linux Lite.
Unfortunately, the Acer setup doesn't have an option for setting the Canadian keyboard layouts, I searched everywhere. It must be done manually, using the solution described in this Keyboard map issue thread in the Software - Linux section.
If you just want to type international characters from time to time, you'd be better of using the Compose key. But that's another debate, and I'm out of time.