I claim the ornamental design for a tabletop sealing device, as shown and described.
FIG. 1 is a perspective view of a tabletop sealing device with the sealing arm in the down position;
FIG. 2 is a top view showing the tabletop sealing device;
FIG. 3 is a front elevational view showing the tabletop sealing device;
FIG. 4 is a side elevational view showing the tabletop sealing device;
FIG. 5 is a side elevational view of the opposed side showing the tabletop sealing device;
FIG. 6 is a rear elevational view showing the tabletop sealing device;
FIG. 7 is a bottom view showing the tabletop sealing device; and,
FIG. 8 is a perspective view showing the tabletop sealing device with the sealing arm in the raised position;
Portions of the tabletop sealing device shown in broken lines in the figures are for illustrative purposes only and form no part of the claimed design.