git-expand

This extension has a content script loaded on github.com/* URLs. It is dormant until the URL is modified to a pull request page, only then it's UI component is mounted. This strategy is required to handle HTML5 history changes used by github links. This UI component scans a pull request page looking for github buttons to load hidden items or hidden conversations. When such button is found the UI shows a floating message describing the hidden content, invokes the button on-click and repeats this process after 1.2 seconds. When all hidden content is loaded the UI will unmount the floating message. If the page had no hidden content the UI would not display any floating message.

Screenshots from Chrome Web Store

Screenshots from Mozilla Add-ons