Just a heads-up - the pixelation used to hide the keys in the final screenshot is not safe! There aren't that many possible characters in each of those 10x10px blocks, and ~256 levels of average brightness is enough to distinguish between them. (Here's a simplistic demo: https://dheera.net/projects/blur)

Stick to the block-of-constant-colour method used in the first few screenshots. It's ugly but safer!