WebXR

See forum post: https://forum.babylonjs.com/t/babylon-editor-export-texture-scaling/12723/26

Reproducible via playground: https://playground.babylonjs.com/#DHZKGW#7

Currently when we export specularGlossiness PBRMaterials via _GLTFMaterialExporter._convertSpecularGlossinessTexturesToMetallicRoughnessAsync

We combine albedo + glossiness textures into Base64 texture string, stripping all

Running the tabs default launch command (-t) does not respect redirects at the target.

$ node . -t https://aframe.io/a-painter

☝️ The above will error, even though the server will redirect to https://aframe.io/a-painter/ and serve HTML there:

$ curl -i https://aframe.io/a-painter
HTTP/1.1 301 Moved Permanently
Date: Mon, 03 Jun 2019 20:10:27 GMT
Content-Type: text/ht

You should be able to add text to a scene. Either as a Text Geometry or SDF text, probably both.

There's already a text component in AFrame that we can use in Hubs. We would need to add a new Spoke node with the ability to preview the text.

I think we should export the following properties:

value
align
anchor
baseline
color
he

Noticed the right half of the keyboard works correctly for transparency during hover, but the left side keys show a black background on hover. The keys circled below are the ones tested as having this issue.

![moonkeyboard](https://user-images.githubuserco

Much like how other multi file resources are uploaded, we want to be able to drag and upload a gltf with associated resource files together into the editor

Use this unzipped contents of this file for test purpose.
glTF-instancing.zip

‘QMutex::QMutex(QMutex::RecursionMode)’ is deprecated: Use QRecursiveMutex instead of a recursive QMutex [-Wdeprecated-declarations]

Related to #1190

Ideally we will have a gltf for each device, but in the meantime we could use a generic VR input device like https://poly.google.com/view/cUT5C1Krx7g or https://poly.google.com/view/0n5B6e5lYZe