The ornamental design for a displayscreen having a graphical user interface or portion thereof, as shown and described.
A portion of the disclosure of this patent document contains material to which a claim for copyright is made. The copyright owner(s) have no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but reserves all other copyright rights whatsoever.
The FIGURE is a front view of a display screen having a graphical user interface or portion thereof.
The dashed broken lines depict portions of the display screen having a graphical user interface or portion thereof and/or the display screen itself and form no part of the claimed design.