glTF mesh is being imported inside out

I’ve made a model in Blender, which looks fine, but if I export as .glb and upload it to the sandbox, all the faces are inside out:

I have already googled around and found out that some normals needed to be flipped, but even after flipping the normals so that the blue side is facing outwards, and after selecting all vertices and recalculating outside, it still appears inside out in the sandbox.

Any idea what’s happening?

Could you try uploading the Blender file?

Here’s the .blend file: Filebin :: bin n0kxcxomfz46c7uy

Here you go! (172.1 KB)

  • Ctrl + A, and Apply All Transforms
  • Turn on Backface Culling in Viewport Shading
  • Go to Edit Mode by pressing Tab
  • Shift + N to Recalculate Normals
  • Export as .glb