The ornamental design for a displayscreen or portion thereof with icon, as shown and described.
FIG. 1 is a front view of a display screen or portion thereof with icon, showing our new design; and,
FIG. 2 is a front view of a display screen or portion thereof with icon, showing an alternative embodiment of the new design.
The broken lines in the figures illustrate the display screen or portion thereof in which the claimed design is embodied. The broken line showing of the display screen or portion thereof illustrates the environment of the claimed design and forms no part thereof.