Dell UltraSharp 38 User Manual page 66

PIP/PBP
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66 Operating the monitor
This function brings up a window displaying images
from another input source. Press the joystick to
confirm the selection.
Main Window
USB-C
USB-C
DP
HDMI 1
HDMI 2
NOTE: The images under PBP mode will be displayed
at the center of the split windows.
Sub-Window
DP HDMI 1 HDMI 2