This extension adds a clear activity indicator when browsing GitHub project pages.
It's often unclear when looking at a GitHub project how much *recent activity* has occurred.
You can check the activity graph, but it's not visible from the project main page and takes times to load.
Sometimes you can see that some files have been recently modified, but it's not obvious if it comes from active development or someone doing superficial changes.
This extension shows an indicator based on a clear metric: the number of commits done in the past 4 weeks. You can see the precise number of commits by hovering the "activity" label, and you can access the full activity graph by clicking on it.
Source (Apache 2.0):