Try setting the display formula option.
In the menu “Tools”, “Options…”, expand “LibreOffice Calc”, select “View” and then under the Display settings enable “Formulae”.
Edit: Adding macro which shows precedents of every cell in the range selected when the macro is executed. This is only a quick attempt and probably in need of some optimisation.
Do NOT select every cell of the worksheet as this will take a very long time as it includes all unused cells.
Sub TraceRangePrecedents()
Dim oRange As Variant
Dim oRangeAddress As Variant
Dim oController As Variant
Dim oDocument As Object
Dim oDispatcher As Object
Dim ic As Integer
Dim ir As Long
Dim sCell As String
oRange = ThisComponent.CurrentSelection
oRangeAddress = oRange.RangeAddress
oController = ThisComponent.CurrentController
oDocument = oController.Frame
oDispatcher = createUnoService("com.sun.star.frame.DispatchHelper")
For ic = oRangeAddress.StartColumn To oRangeAddress.EndColumn
For ir = oRangeAddress.StartRow To oRangeAddress.EndRow
oController.select(oRange.Spreadsheet.getCellByPosition(ic, ir))
oDispatcher.executeDispatch(oDocument, ".uno:ShowPrecedents", "", 0, Array())
Next ir
Next ic
oController.select(oRange)
End Sub
