Is uniqueName a supported property?

Hi,
I'm working on something that requires that I create an AAD app registration with a uniqueName property. The only way that they've told me I can assign my app registration a uniqueName is with some strange script that doesn't seem to work. Is there a more formal way of setting the uniqueName?

Thanks!

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#### Document Details

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* ID: 921aa920-c25f-5227-aabb-49116da38fa7
* Version Independent ID: 9b5a53ad-edf8-4d89-f8e6-cde01b7866f6
* Content: [az ad app](https://docs.microsoft.com/en-us/cli/azure/ad/app?view=azure-cli-latest)
* Content Source: [latest/docs-ref-autogen/ad/app.yml](https://github.com/MicrosoftDocs/azure-docs-cli/blob/main/latest/docs-ref-autogen/ad/app.yml)
* Service: **active-directory**
* GitHub Login: @rloutlaw
* Microsoft Alias: **routlaw**