The ornament design for a logotoothbrushholder, as shown and described.
FIG. 1 is a perspective view of as logo toothbrush holder showing our new design;
FIG. 2 is a front view thereof;
FIG. 3 is a back view thereof;
FIG. 4 is a side view; the opposite side view is a mirror-image thereof;
FIG. 5 is a top view thereof; and,
FIG. 6 is a bottom view thereof.
In FIGS. 1 and 2, the broken lines showing the environmental structure for purposes of illustrating the logo toothbrush holder in a condition of use. The broken lines and the structure they depict form no part of the claimed design.