Found in

• Firefox 106.0b8

Affected versions

• Firefox 105.0.2
• Firefox 106.0b8
• Nightly 107.0a1
• 102.3.0esr

Affected platforms

• Windows 10
• macOS 13

Steps to reproduce

1. Launch Firefox and access any webgl / nodes demo video such as:
   https://threejs.org/examples/#webgl_nodes_loader_gltf_sheen
   https://threejs.org/examples/#webgl_nodes_points

Expected result

• The webgl / nodes demo videos should be rendered properly.

Actual result

• A back screen is displayed.

Regression range

*Not a recent regression because the issue can be reproduced in Nightly 66.0a1.

:epopescu, if you think that's a regression, could you try to find a regression range using for example mozregression?

Error in Webconsole:

20:31:29.426 Uncaught TypeError: Error resolving module specifier “three”. Relative module specifiers must start with “./”, “../” or “/”. webgl_nodes_loader_gltf_sheen.html:37:26
20:31:33.637 Uncaught SyntaxError: import not found: mul 64734247-b414-44bb-9ed0-aa88a8767614:2:37
    loadPromise https://unpkg.com/es-module-shims@1.3.6/dist/es-module-shims.js:766
    (Async: setTimeout handler)
    loadPromise https://unpkg.com/es-module-shims@1.3.6/dist/es-module-shims.js:766
    (Async: promise callback)
    processScript https://unpkg.com/es-module-shims@1.3.6/dist/es-module-shims.js:765
    processScriptsAndPreloads https://unpkg.com/es-module-shims@1.3.6/dist/es-module-shims.js:667
    initPromise https://unpkg.com/es-module-shims@1.3.6/dist/es-module-shims.js:376
    (Async: promise callback)
    <anonymous> https://unpkg.com/es-module-shims@1.3.6/dist/es-module-shims.js:340
    <anonymous> https://unpkg.com/es-module-shims@1.3.6/dist/es-module-shims.js:789

The site uses <script type="importmap">
( https://html.spec.whatwg.org/multipage/webappapis.html#import-maps )

If set dom.importMaps.enabled to true then it works.

Import-maps is still off by default.
Please try to enable it and re-run it again.
pref: dom.importMaps.enabled

The issue no longer persists when enabling the pref dom.importMaps.enabled(set to true) and the webgl / nodes demo videos are loaded properly.
I've checked on Firefox 105.0.3 and Nightly 107.0a1, both on Windows 10 and macOS 13.
Marking it as RESOLVED:WORKSFORME.