TabItemView-minimal.swift

final class TabItemView: NSView {
    let tab: Tab
    var onTabHover: ((Int) -> Void)?
    
    private var firstColumnLabel: NSTextField
    private var seconColumnLabel: NSTextField

    public var swipeActionViewCenterYAnchorConstraint = NSLayoutConstraint()
    
    private var isRunningFullSwipe = false
    private var isRunningPartialFullSwipe = false
    private var isRunningAnyAnimation = false
    
    private var totalSwipeDistance: CGFloat = 0
    
    /// need to lock on swipe-to-close-tab scroll and avoid letting user to swipe vertically
    private var isUserTryingToSwipeToCloseTab = false
    
    private var textLabelForSwipeViewXConstraint = NSLayoutConstraint()
    
    init(tab: Tab) {
        self.tab = tab
        
        switch appState.columnOrder {
        case .host_title:
            self.firstColumnLabel = NSTextField(labelWithString: tab.host)
            self.seconColumnLabel = NSTextField(labelWithString: tab.title)
        case .title_host:
            self.firstColumnLabel = NSTextField(labelWithString: tab.title)
            self.seconColumnLabel = NSTextField(labelWithString: tab.host)
        }
        
        let textLabelForSwipeView = NSTextField(labelWithString: Copy.TabsPanel.closeButtonTitle)
        let stackView = NSStackView()
        
        super.init(frame: .zero)
        
        self.clipsToBounds = true
        self.wantsLayer = true
        self.layer?.cornerRadius = 6
        
        textLabelForSwipeView.font = .systemFont(ofSize: 13, weight: .regular)
        textLabelForSwipeView.textColor = .white
        
        firstColumnLabel.lineBreakMode = .byTruncatingTail
        firstColumnLabel.setContentCompressionResistancePriority(.defaultLow, for: .horizontal)
        firstColumnLabel.font = .systemFont(ofSize: 18)
        firstColumnLabel.textColor = .tabFg
        
        stackView.orientation = .horizontal
        
        stackView.edgeInsets = .init(top: 0, left: 57, bottom: 0, right: 50)
        stackView.addArrangedSubview(firstColumnLabel)
        
        stackView.translatesAutoresizingMaskIntoConstraints = false
        
        self.addSubview(stackView)
        
        NSLayoutConstraint.activate([
            stackView.leadingAnchor.constraint(equalTo: leadingAnchor),
            stackView.trailingAnchor.constraint(equalTo: trailingAnchor),
            stackView.topAnchor.constraint(equalTo: topAnchor),
            stackView.bottomAnchor.constraint(equalTo: bottomAnchor),
        ])
    }

    required init(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}

Here is the TabHistoryView.swift which works with this TabItemView class:

https://gist.github.com/kopyl/693773388d4e944bdc401561d665b215