Your minified js code indicates that there is a source map: ```javascript //# sourceMappingURL=app.js.map ``` But your web host returns a 404 for it (https://stefan-oltmann.de/oni-seed-browser/app.js.map).
Your minified js code indicates that there is a source map:
//# sourceMappingURL=app.js.mapBut your web host returns a 404 for it (https://stefan-oltmann.de/oni-seed-browser/app.js.map).