У вашего броузера проблема в совместимости с HTML5
For Blender 2.80 and later, get Loopanar: https://sourceforge.net/projects/blendamajigs/files/loopanar/
Help page: https://sourceforge.net/p/blendamajigs/wiki/Loopanar/
For Blender 2.79, download the Zaloopok addon: https://sourceforge.net/projects/blenderbitsbobs/files/
Help page: https://sourceforge.net/p/blenderbitsbobs/wiki/Zaloopok/