У вашего броузера проблема в совместимости с HTML5
In 7 days to day A17 you can add item_modifiers to hand items like weapons, and this is a short video on how to create your own in Unity. You can find my Salvaged Bats modlet on my repo at: https://github.com/7D2D/A17Mods In that mod you will find the xml referenced in this video. (Apologies in advance for the occasional breathing noise as I moved the mike too close to make the audio louder)