src/vs/platform/extensions/common/extensions.ts/getWorkspaceSupportTypeMessage
export function getWorkspaceSupportTypeMessage(supportType: ExtensionUntrustedWorkspaceSupport | ExtensionVirtualWorkspaceSupport | undefined): string | undefined {
	if (typeof supportType === 'object' && supportType !== null) {
		if (supportType.supported !== true) {
			return supportType.description;
		}
	}
	return undefined;
}