             // keeping all existing JS in place.
             webVC?.wkUserContentControllerTestingConfigurationBlock = { userContentController in
                 // Add self as 'jsTesting' script message handler.
-                userContentController.add(self, name: self.jsTestingMessageHandlerString)
+                userContentController.add(self, name: self.testFirstSectionAppearanceMessageHandlerString)
                 
                 // This message will be sent as soon as the web view inflates the DOM of the index.html (before our
                 // sections are injected).
-                let startTimeJS = "window.webkit.messageHandlers.\(self.jsTestingMessageHandlerString).postMessage('\(self.startTimeMessageString)')"
+                let startTimeJS = "window.webkit.messageHandlers.\(self.testFirstSectionAppearanceMessageHandlerString).postMessage('\(self.testFirstSectionAppearanceStartTimeMessageString)')"
                 userContentController.addUserScript(
                     WKUserScript.init(source: startTimeJS, injectionTime: .atDocumentEnd, forMainFrameOnly: true)
                 )

        super.tearDown()
    }

    let jsTestingMessageHandlerString = "jsTesting"
    let startTimeMessageString = "startTime"
    let firstSectionAppearedMessageString = "firstSectionAppeared"
    
    func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
        // print("\n \n \n message body : \(message.body) \n \n \n ")

                let tenMillisecondPollingJS = """
                const checkFirstSectionPresence = () => {
                   if(document.querySelector('#section_heading_and_content_block_0')){
                       window.webkit.messageHandlers.\(self.testFirstSectionAppearanceMessageHandlerString).postMessage('\(self.testFirstSectionAppearedMessageString)')
                   }else{
                       setTimeout(checkFirstSectionPresence, 10 )
                   }
