Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The lost read-only property of the GPUDevice interface contains a Promise that remains pending throughout the device's lifetime and resolves with a GPUDeviceLostInfo object when the device is lost.
GPUAdapter.requestDevice() will never return null, and it will reject only if the request is invalid, i.e. it exceeds the capabilities of the GPUAdapter. If a valid device request can't be fulfilled for some reason however it may resolve to a device that has already been lost. Additionally, devices can be lost at any time after creation for a variety of reasons (such as browser resource management or driver updates), so it's a good idea to always handle lost devices gracefully.
Many causes for lost devices are transient, so you should try getting a new device once a previous one has been lost unless the loss was caused by the application intentionally destroying the device (i.e. with GPUDevice.destroy()). Note that any WebGPU resources created with a previous device (buffers, textures, etc.) will need to be re-created with the new one.
Note: Also bear in mind that a GPUAdapter may become unavailable, e.g. if the physical GPU is unplugged from the system or disabled to save power. From then on, the adapter can no longer return valid devices, and will always return already-lost devices.