Handling lazy-loading webpages using vba
You may want to try this below. First is to try reduce loading times, especially images and videos when scrolling down. Then have a counter to count number of "StretchedBox" elements before the scroll down, then check up to a few more attempts until no more changes (I used 5 in code). You can remove the Debug lines in final version.

Note some "StretchedBox" isn't really an article headline (video related), you will need to work on those to filter out junk.

Option Explicit

Sub Web_Data()
    Const TITLES As String = "StretchedBox"
    Dim sh As Object, regval As String

    ' Change IE Options
    Set sh = CreateObject("WScript.Shell")
    regval = "HKCU\Software\Microsoft\Internet Explorer\Main\Display Inline Images"
    sh.RegWrite regval, "no", "REG_SZ"
    regval = "HKCU\Software\Microsoft\Internet Explorer\Main\Enable Browser Extensions"
    sh.RegWrite regval, "no", "REG_SZ"
    regval = "HKCU\Software\Microsoft\Internet Explorer\Main\Play_Animations"
    sh.RegWrite regval, "no", "REG_SZ"
    regval = "HKCU\Software\Microsoft\Internet Explorer\Main\EnableAlternativeCodec"
    sh.RegWrite regval, "no", "REG_SZ"

    ' Prepare IE
    Dim IE As New InternetExplorer, html As HTMLDocument
    Dim posts As Object, sText As String
    Dim TitlesCount As Long, NoChangesCount As Integer, Row As Long

    With IE
        .Visible = True
        .navigate "https://finance.yahoo.com/"
        Debug.Print Now, "Navigated Start"
        Do Until .readyState = READYSTATE_COMPLETE: Loop
        Debug.Print Now, "Navigate Complete"
        Set html = .document
    End With
    NoChangesCount = 0
    On Error Resume Next
    Do
        DoEvents
        Application.Wait Now() + TimeValue("00:00:02")
        ' Remove all the annoying video parts
        RemoveVideos html
        TitlesCount = GetClassCount(html, TITLES)
        Debug.Print Now, TitlesCount
        html.parentWindow.scrollBy 0, 99999
        If TitlesCount = GetClassCount(html, TITLES) Then
            NoChangesCount = NoChangesCount + 1
        Else
            NoChangesCount = 0
        End If
    Loop Until NoChangesCount = 5 ' If no changes for some attempts, assume end of dynamic page
    On Error GoTo 0
    Columns("A").ClearContents
    For Each posts In html.getElementsByClassName(TITLES)
        sText = WorksheetFunction.Clean(posts.ParentNode.innerText)
        'sText = Trim(posts.ParentNode.innerText)
        If Len(sText) &gt; 0 Then
            Row = Row + 1
            Cells(Row, 1).Value = sText
        End If
    Next posts
    IE.Quit
    ' Restore IE Options
    regval = "HKCU\Software\Microsoft\Internet Explorer\Main\Display Inline Images"
    sh.RegWrite regval, "yes", "REG_SZ"
    regval = "HKCU\Software\Microsoft\Internet Explorer\Main\Enable Browser Extensions"
    sh.RegWrite regval, "yes", "REG_SZ"
    regval = "HKCU\Software\Microsoft\Internet Explorer\Main\Play_Animations"
    sh.RegWrite regval, "yes", "REG_SZ"
    regval = "HKCU\Software\Microsoft\Internet Explorer\Main\EnableAlternativeCodec"
    sh.RegWrite regval, "yes", "REG_SZ"
    Set sh = Nothing
End Sub

Private Function GetClassCount(Doc As HTMLDocument, ClassName As String) As Long
    GetClassCount = Doc.getElementsByClassName(ClassName).Length
End Function

Private Sub RemoveVideos(Doc As HTMLDocument)
    Dim oElement As Object
    For Each oElement In Doc.getElementsByClassName("yvp-main")
        oElement.innerHTML = ""
    Next
End Sub