This is a GMail extension that allows for keyboard shortcut macros in your inbox. There are currently three types of macros you can build and map to keys. One allows you to highlight messages with certain senders, another allows you to hightlight messages with certain keywords in the subject. The third allows you to map a keyboard shortcut to emailing a group of people.
There is a file called Sara.js, it contains my custom settings. You will need to create one of your own, add your settings, and also add it to the array of content scripts contained in manifest.json.
The goal of this extension is to add to it as I find the need/solution. Enjoy!!