Your project does not rely on the es6 version @babylonjs/… of npm and is using atm the min version of Babylon which does not have a map file as we discussed earlier.
You need to either change your dependency or use the max version of babylon delivered in the npm packages.
To do so use alias setup in Webpack:
extensions: [’.tsx’, ‘.ts’, ‘.jsx’, ‘.js’, ‘.json’],
“babylonjs”: path.resolve(__dirname, ‘node_modules/babylonjs/babylon.max.js’),
“babylonjs-loaders”: path.resolve(__dirname, ‘node_modules/babylonjs-loaders/babylonjs.loaders.js’)
and also, fix your sourceMapDevPlugin:
and do not embed a second d.ts file for babylon as it is creating a lot of dupplicate errors in TS.