In this case, the ISP blocked it because the website is anna's archive [2], which was blocked around a year ago, but they have not made a post about that.
If you put "pcm." in front of the link it will work (for now)
You should probably edit your post, so as not to misinform. But I have to admit this confusion stems from bad decisions at the ISP.
[1] https://www.ziggo.nl/website-geblokkeerd
[2] https://en.wikipedia.org/wiki/Anna%27s_Archive#Netherlands
I've got a different, (not meta) VR HMD, and am running things using Envision and Stardust XR.
Excuse me if none of this applies to mixed reality.
Will you provide source code anywhere?