Helpo de LibreOffice 24.8
Vertically aligns the bottom edges of the selected objects. If only one object is selected in Draw or Impress, the bottom edge of the object is aligned to the lower page margin.
Objects are aligned to the bottom edge of the bottom most object in the selection. To align the individual objects in a group,
to enter the group, select the objects, right-click, and then choose an alignment option.