The ornamental design for a displayscreen or portion thereof with icon, as shown and described.
FIG. 1 is an enlarged front view of a first embodiment of the display screen or portion thereof with icon shown independent to the graphical user interface from FIG. 2; and,
FIG. 2 is a front view of a display screen or portion thereof with icon showing our new design as part of an environmental graphical user interface.
The dash-dot broken lines in the drawings illustrate the display screen or portion thereof that forms no part of the claimed design. Moreover, the even broken line showing the landscape background, various text and surrounding dashboard widgets are provided for the purpose of illustrating environmental structure of a graphical user interface and forms no part of the claimed design.