Your own script probably runs before pixi is loaded. Can you try <script defer>your code </script>

I would suggest to do this on a separate html page and not from within the Unity game. Then you can just use a normal html file upload form, you don’t need any plugin. developer.mozilla.org/en-US/docs/Web/HTML/Element/input/file

It seems that express-handlebars creates HTML on the server and then sends the whole html page back to the browser. So you should be able to submit the form normally instead of using fetch. If you do want to use fetch you'll have to handle the result after fetch returns something. (by using then().)

Can you add the whole code in your question, not as an image? Is there a reason why you use fetch and arrayBuffer to load a video, instead of directly setting the src of a <video> element?

I think you need to post a code example where it shows why height:100% doesn't work for you.

You could include the siblings/spouses from the dataset in your training

@DrewReese I've read this whole page several times, but it's still not clear to me what the bug in my code could possibly be. Do I have to solve it? Is this expected behaviour in React? It seems even React experts don't have a definitive answer.

Some articles explain @property but that doesn't seem to be widely supported? developer.mozilla.org/en-US/docs/Web/CSS/@property

You are correct :) I did not know that :) But I was able to hack it by setting the animation as a string: foo.style.animation = "my-animation 2s forwards" and then keeping the actual keyframe animation in the stylesheet: jsfiddle.net/3roed9qv

Also I believe that CSS variables are only evaluated once at the start of the page build. Changing the variable later has no effect (as far I as I understand).

Have you looked at 3D transforms? w3schools.com/css/css3_3dtransforms.asp

Maybe create another build in a dedicated folder, and then you can check what new files were created?