How to hide the disclosure indicator in macOS MenuBar app

Question

I have a macOS SwiftUI menu bar app. I'm trying to figure out how to get rid of this disclosure triangle. The code for the popover is below.

private func setupStatusBarItem() {
    statusBarItem = NSStatusBar.system.statusItem(withLength: CGFloat(NSStatusItem.variableLength))
    configureStatusBarButton()
}

private func configureStatusBarButton() {
    if let button = statusBarItem.button {
        button.image = NSImage(named: "icon")
        button.action = #selector(togglePopover(_:))
    }
}

@objc func togglePopover(_ sender: AnyObject?) {
    if let button = statusBarItem.button {
        if popover.isShown {
            popover.performClose(sender)
        } else {
            popover.show(relativeTo: button.bounds, of: button, preferredEdge: NSRectEdge.minY)
        }
    }
}

private func setupPopover() {
    let contentView = ContentView(viewModel: viewModel, appDelegate: self)
    popover = createPopover(with: contentView)
}

private func createPopover(with contentView: ContentView) -> NSPopover {
    let popover = NSPopover()
    popover.contentSize = NSSize(width: 300, height: 250)
    popover.behavior = .transient
    popover.contentViewController = NSHostingController(rootView: contentView)
    return popover
}