WPT details: WebGPU/WGSL have a conformance test suite (https://github.com/gpuweb/cts) that is regularly pulled into Chromium and part of the testing of Dawn/Tint in Chromium. While the CTS can be embedded in WPT, the WebGPU team opted to keep it separate in Chromium testing to use a customized harness for robustness and performance. All the tests about this feature in WebGPU CTS can be found at https://github.com/gpuweb/cts/issues/2356
Functionality added to the WebGPU spec after its first shipment in a browser. The GPUAdapterInfo isFallbackAdapter boolean attribute indicates if an adapter has significant performance limitations in return for wider compatibility, more predictable behavior, and/or improved privacy. Note that a fallback adapter may not be present on all systems.
The GPUAdapter isFallbackAdapter boolean attribute currently shipped in Chrome browser only does not allow libraries that take user-provided GPUDevice objects from accessing this information through the adapterInfo attribute on GPUDevice. Adding a GPUAdapterInfo isFallbackAdapter boolean attribute solves this problem. Note that GPUAdapter isFallbackAdapter usage is being measured to determine if it can be deprecated and removed, as Chrome has not yet shipped support for fallback adapters. https://github.com/gpuweb/gpuweb/pull/5099