The ornamental design for a footprintkeepsakedisplay, as shown and described.
FIG. 1 is a front elevation view of a footprint keepsake display showing our new design;
FIG. 2 is a rear elevation view thereof;
FIG. 3 is a left side elevation view thereof;
FIG. 4 is a right side elevation view thereof;
FIG. 5 is a top plan view thereof;
FIG. 6 is a bottom plan view thereof; and,
FIG. 7 is an isometric view thereof.
The broken-line showing of text, numerals, a footprint and a shoe in the figures illustrate environmental subject matter that forms no part of the claimed design.