Sebavan has a good point with the repro, though as a best practice if your loading from a model file you should use glTF and then do something like this for loading:
where gltfString is the contents of our glTF file - this also allows us to do
new Blob([fileContents]).text().then(data=>{
//SceneLoader Here
});
This might clear up your problems by using glTF. I also noticed that the error refers to data:data:... so maybe check their isn’t something like "data:"+dataString where dataString also has data: