I have published an app and editing it. One new "Rev" tab is created and it is giving me a dropdown as shown here![enter image description here][1]. Why it is being created here? It is not created in any other Stack Exchange websites when we edit question. Is it related to <!-- version: 0.0 --> as explained here: https://stackapps.com/q/7? [1]: https://i.sstatic.net/iSQtj.png