The file explorer allows users to see what parts of an application are most active in source control history, and by whom. This feature is accessed by clicking the "folder" icon next to a repository in the repository list, or from the repository detail page.
The view is subject to the time range selected, so it is easy to compare development activity trends from year to year. This view could be a way for new employees to figure out who is the expert in a particular area of the code, and can be thought as a time-sensitive version of "git praise" and "git blame", but on a file and directory level scope.
The file explorer is somewhat basic, and may melt your CPU while trying to access it. It seems to work best in Chrome.