$ curl cheat.sh/
# xprop
# A tool for displaying window and font properties in an X server.
# More information: <https://manned.org/xprop>.

# Display the name of the root window:
xprop -root WM_NAME

# Display the window manager hints for a window:
xprop -name "window_name" WM_HINTS

# Display the point size of a font:
xprop -font "font_name" POINT_SIZE

# Display all the properties of the window with the id 0x200007:
xprop -id 0x200007

$
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