Hiding the New and Upload buttons from a SharePoint document library using JSON list formatting

Recently I got a query about hiding the New and Upload buttons for a SharePoint library, because there was a need to allow users to browse documents using out-of-the-box SharePoint views in a library while still having permissions to upload files so that they could upload files using an SPFx WebPart or a Canvas App.

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Background from Microsoft - Command bar customization syntax reference

The JSON-based functionality enables simple adjustments to the command bar, such as changing the icon or text, hiding already-existing options, or moving commands.

https://learn.microsoft.com/en-us/sharepoint/dev/declarative-customization/view-commandbar-formatting?WT.mc_id=M365-MVP-5004644