         super.tearDown()
     }
 
-    let jsTestingMessageHandlerString = "jsTesting"
-    let startTimeMessageString = "startTime"
-    let firstSectionAppearedMessageString = "firstSectionAppeared"
+    let testFirstSectionAppearanceMessageHandlerString = "testFirstSectionAppearance"
+    let testFirstSectionAppearanceStartTimeMessageString = "startTime"
+    let testFirstSectionAppearedMessageString = "firstSectionAppeared"
     
     func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
         // print("\n \n \n message body : \(message.body) \n \n \n ")

        }
        
        switch message.name {
        case jsTestingMessageHandlerString:
            switch messageString {
            case startTimeMessageString:
                startTimeMessageReceivedExpectation?.fulfill()
            case firstSectionAppearedMessageString:
                firstSectionAppearedMessageReceivedExpectation?.fulfill()
            default:
                return

            // keeping all existing JS in place.
            webVC?.wkUserContentControllerTestingConfigurationBlock = { userContentController in
                // Add self as 'jsTesting' script message handler.
                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.testFirstSectionAppearanceMessageHandlerString).postMessage('\(self.testFirstSectionAppearanceStartTimeMessageString)')"
                userContentController.addUserScript(
                    WKUserScript.init(source: startTimeJS, injectionTime: .atDocumentEnd, forMainFrameOnly: true)
                )
