I would imagine that this can be easily converted into a GreaseMonkey userscript. Since you have chosen to implement this for Chrome, the question which naturally comes to my mind is - is it even easier to write these addons for Chrome than writing an userscript?
Firefox user here, considering to switch for some time.
OP here. I have never worked on a GreaseMonkey script before...only used a Chrome extension because it seemed to fit the project requirements and it was the first thing that came to mind.
That said, I did find it extremely easy to create a Chrome extension. Really nice to have access to the DOM straight through javascript. Check out the source code for this extension...only took a few lines to write the actual logic
Firefox user here, considering to switch for some time.