Status button highlight when popover is active (Swift, macOS)

Question

I am making a status bar macOS app. On clicking on the status bar icon, I am showing an NSPopover (not an NSMenu). However, when my NSPopover is shown, my status menu icon is not highlighted. It is only highlighted for a moment when I click it. I want it to stay highlighted, much like how it behaves with the wifi status bar icon.

I know that if I use a NSMenu instead of a NSPopover, it can probably be fixed. But the requirement is such that I need to use a NSPopover.

I have tried the following approaches, but to no avail:

1.

let statusItem = NSStatusBar.system.statusItem(withLength:NSStatusItem.squareLength)
if let button = statusItem.button {
    button.setButtonType(.pushOnPushOff)
}

statusItem.highlightMode = true

statusItem.button?.highlight(true)

statusItem.button?.isHighlighted = true

I am not very experienced with status bar apps. So I am not really sure about which approach to take here.

The left most icon is my status bar app icon. The popover is currently active but the icon is not highlighted. I had to crop out the popover.