The site http://crashsafari.com freezes Firefox even on strong hardware. This bug can also be found on Google Chrome. However, Safari patched this issue. The aforementioned bug can also be found in the latest Nightly 55. I can reproduce by following these steps: 1. Start Firefox by clicking on the desktop icon 2. Press Cmd+N (or Ctrl+N for Windows users) to open a new browser window 3. Paste https://crashsafari.com/ in the address bar and press Enter. Expected results: The site should load. Actual results: The site loads infinately and freezes Firefox. Moreover, the CPU usage is 100% and the rest of the system is busy and functions as expected. As I said before, the issue is persistant, which means that firefox hangs a long time and needs to be closed with force via the Task Manager. On Linux, firefox needs to be closed via kill -n.

In general, these demo websites are useless as there are many ways to make Firefox freeze when using a ton of memory with loop in simple JS code.

OK. Shall I close this bug report then?