У вашего броузера проблема в совместимости с HTML5
Here it is, the 1.14.4 Tutorial for Litematica! I did leave a couple bloopers in the video due to how long the segment of the video was. Hopefully you find this useful since a couple of things have changed since the last tutorial.
Ask any questions you have below, I will answer them as well as I can - one thing I am not sure of is the maximum size of schematic files.
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