How can I determine the names and default values of the formatting options provided by the C#/OmniSharp extension for Visual Studio Code?

I am creating an omnisharp.json file to set my C# formatting preferences. How do I know what properties are available to set and what their default values are?

• I can press Ctrl + Space to display IntelliSense and that suggests some properties, but not all of them. For example, the recent v1.21.10 mentions support for organizing using statements, however IntelliSense doesn't seem to know about the corresponding OrganizeImports property.
• There is supposedly a config.json file in the extension's OmniSharp directory that specifies the default settings, but I don't have such a file.
• The Configuration Options wiki page for the omnisharp-roslyn project lists a default FormattingOptions block, but it is also missing OrganizeImports.
• There is an entry for omnisharp.json on SchemaStore.org, but if you look at that same file in the SchemaStore GitHub repository you see it hasn't been updated in over three years.
• An oft-linked blog article for configuring omnisharp.json is C# code formatting settings in VS Code and OmniSharp. Though that article lists default formatting settings, it is also over three years old.

Surely there must be either a definitive, up-to-date source of this information or a way I can determine it myself, right?