Display Panel or Portion Thereof with Graphical User Interface

This patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee. FIG. 1 is a front view of a display panel or portion thereof with graphical user interface according to a first embodiment of our new design; FIG. 2 is another front view of FIG. 1 ; FIG. 3 is a front view of a second embodiment thereof; and, FIG. 4 is another front view of FIG. 3 . The outermost broken lines in FIGS. 2 and 4 depict a mobile device, which is the environment of the design and form no part of the claimed design. The dot-dashed broken lines depict the display screen and the boundary of the design, and form no part of the claimed design. The remaining dashed broken lines depict portions of the graphical user interface that form no part of the claimed design.