https://books.libreoffice.org/en/CG71/CG7108-PivotTables-img/CG7108-PivotTables-img020.png The depicted dialog shows title "Data Field Options" although it does not apply to data fields. It should be titled "Column Field Options" or "Row Field Options" respectively.
Pivot table uses same dialog for columns, row, filter and data. https://opengrok.libreoffice.org/xref/core/sc/uiconfig/scalc/ui/datafieldoptionsdialog.ui The dialog controller should then distinguish between columns, row, filter and data, to change the dialog title text.
(In reply to Olivier Hallot from comment #1) > The dialog controller should then distinguish between columns, row, filter > and data, to change the dialog title text. Yes, it should. It is ScDPFunctionDlg with sc/uiconfig/scalc/ui/datafielddialog.ui but I don't know how the dialog is started. Actually even the frame title being either Function or Subtotals is a miracle.