View Issue/Pull Request Buttons for Gmail
github.comWe set this up for Meldium a little while ago and our customers love it. We wrote up a HOWTO here: http://blog.meldium.com/home/2014/5/19/setting-up-gmail-inbo...
As did we at Rainforest! It's a nice little detail and a pretty easy hack: https://blog.rainforestqa.com/2014-04-24-howto-gmail-action-...
So thats what those are! I started noticing these buttons last week with my subscriptions. Looks like Mailchimp wrote a blog post about it too - http://blog.mailchimp.com/gmails-inbox-actions-work-with-mai...
Before you start implementing this for your own services, make sure you meet the guidelines[1] for being approved by Google. Specifically, you must have a history of sending hundreds of emails a day to gmail users.
This isn't for small projects (yet, at least).
[1] https://developers.google.com/gmail/actions/registering-with...