     private var activeUserCount = 0
     private var maxActiveUserCount = 0
     private var activeUserHistory: [(Date, Int)] = []
+
+    private var cellViewFlashed: [String: Bool] = [:]
 
     // AuthWindowController
     private lazy var authWindowController: AuthWindowController = {

        }
        let color = HandleNameManager.shared.color(for: chat.userId, in: live.communityId)
        view.setBackgroundColor(color)
        if [.emotion, .gift, .nicoad].contains(chat.slashCommand) {
            view.flash(NSColor.red)
        } else {
            view.cancelFlash()
        }
    }

    // MARK: Utility
    private func contentAndAttributes(forMessage message: Message) -> (String, [String: Any]) {

        view.cancelFlash()
    }

    // swiftlint:disable function_body_length
    private func configure(view: NSTableCellView, forChat message: Message, withTableColumn tableColumn: NSTableColumn) {
        guard let live = live, case let .chat(chat) = message.content else { return }

