The hang of Preview with file auto-save (<experimental) enabled when e.g. the intermediate state of entered code is an infinite JS loop is I guess known.
Once I’ve killed the browser, when I reopen the project, the Preview tab reappears with page show and promptly hangs again.
Please consider showing the safe http://i.imgur.com/C7cTxX6.png instead.
- Be very quick in closing the Preview tab before the hang.
- Clone the project. The clone opens with Prievew showing the safe http://i.imgur.com/C7cTxX6.png