I hope GitHub leaps on the opportunity to integrate this:

The Browser Integrated Testing Environment, or BITE, is an open source Chrome Extension which aims to fix the manual web testing experience.… When filing a bug, BITE automatically grabs screenshots, links, and problematic UI elements and attaches them to the bug.…

…[E]very action the tester takes on the page is recorded in JavaScript, and can be played back later. This enables engineers to quickly determine if the steps of a bug repro in a specific environment, or whether a code change has resolved the issue.

Also included in BITE is a Record/Playback console to automate user actions in a manual test.

"Take a BITE out of Bugs and Redundant Labor" (Google Testing Blog)