jones_supa writes The lack of a vertical tab strip (or "Tree Style Tab" as the Firefox extension is called) has been under a lot of discussion under Chrome/Chromium bug tracker. Some years ago, vertical tabs existed as an experimental feature enabled with a "secret" command line parameter, but that feature was eventually removed from the browser. Since then, Google has been rather quiet about whether such feature is still on the roadmap. Now, a Google engineer casts some light on the issue. He says that a tree-style interface for tabs would be overly complex as a native implementation, but Google would back the idea of improving the extensions interface to support a sidebar-like surface to render the tab UI on, if someone from the open source community would step forward to do the work to drive the feature to completion.