The ornamental design for an appliancedoorholder, as shown and described.
FIG. 1 is a perspective view of an appliance door holder showing my new design.
FIG. 2 is a top plan view thereof.
FIG. 3 is a left side elevational view thereof.
FIG. 4 is a front elevational view thereof, the rear view being a mirror image thereof.
FIG. 5 is a right side elevational view thereof; and,
FIG. 6 is a bottom plan view thereof.
The broken lines illustrating portions of the appliance door holder are for the purpose of illustrating portions that form no part of the claimed design.