Clicking on the hamburger menu 
on a card brings up the Action Menu.
From the Action Menu you can:
...
As of version 5 of Inbox for Jira the quick links was introduced to allow quick actions such as:
- Vote / Unvote
- Watch / Unwatch
- Comment
- Approve / Decline service desk issues (only available if JIRA service desk is used)
Example of quick links :
Prior to version 5, these options were in a separate hamburger menu on each notification card.