convert unicode image to object url JS

I’m really stuck at converting a PNG image from unicode (I think) to an object URL. I’m using Vue js to convert it. The data is returned by a .NET application using

return new FileContentResult(ms.ToArray(), "image/png");

In my frontend / client app, I can see that I receive this response
enter image description here

But what now? 🙂 I tried a lot of things, without any luck. I’m not too familiar with these types of conversion… I did it once and completely forgot how.

ps: If I use Postman, the image is loaded correctly.