У вашего броузера проблема в совместимости с HTML5
Seamly2D - Beginners tutorial in English, however is suitable for all languages since there is no sound.
Using Seamly2D to create a sewing pattern from a diagram.
I used the image from this blog: https://dulcemariadiy.blogspot.com/2017/07/como-hacer-un-body-con-volado-circular.html