For example, this does not work:
https://slicer-packages.kitware.com/api/v1/app/5f4474d0e1d8c75dfc705482/extension
And entering on the extensions manager I see this:
[Qt] An OpenGL Core Profile was requested, but it is not supported on the current platform. Falling back to a non-Core profile. Note that this might cause rendering issues.
[FD] DevTools listening on ws://127.0.0.1:1337/devtools/browser/e3ac763f-981b-4330-8648-83f0249ecfe5
[Qt] Remote debugging server started successfully. Try pointing a Chromium-based browser to http://127.0.0.1:1337
[Qt] "https://extensions.slicer.org/js/chunk-vendors.faf86a0d.js" 7 "Uncaught (in promise) Error: Network Error"
[Qt] Uncaught (in promise) Error: Network Error
I have Slicer stable release 5.6.2