I claim the ornamental design for a footwear sole, as shown and described.
FIG. 1 is a bottom perspective view of a footwear sole embodying my new design;
FIG. 2 is a bottom plan view thereof;
FIG. 3 is a right side elevational view thereof, shown at a reduced scale;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a front elevational view thereof, shown at an enlarged scale; and,
FIG. 6 is a rear elevational view thereof.
FIGS. 1–6 show features of an article of footwear in phantom lines. These features are shown for environmental purposes and do not form any part of the claimed design. Further, the phantom lines immediately adjacent the solid-line portions of the design form the boundary of the design, with the phantom lines forming no part of the claimed design.