If you frequently use your laptop with more than one external display, there's a feature called MST (or Multi-Stream Transport) that conveniently allows you to use just one cable to connect them all to your computer, rather than two or three. Up until now Chrome OS hasn't supported MST, but based on a recent commit to the Chromium Gerrit, that could change.
MST isn't a new technology by any means, it was introduced with the nearly decade-old DisplayPort v1.2 spec, though daisy-chaining displays together probably isn't common practice among general consumers. But for more technical folks with complex, multi-monitor workflows, it can be a useful tool, especially when toting a laptop between workstations.
Right now, the commit in question is specific to an upcoming device with the board name "hatch," enabling the functionality quite explicitly for testing purposes. At this early stage, it isn't clear if MST will be coming to older devices or if it's simply being planned for "hatch"-based devices going forward — there is a hardware requirement explicitly mentioned in the commit, and it's possible older devices may not meet it.
- Chromium Gerrit
- Chrome Unboxed