XGetWMColormapWindows(3) on Linux
The text fa151b205f8e, as Debian 11 (Bullseye) shipped it.
set or read a window's WM_COLORMAP_WINDOWS property
The text fa151b205f8e, as Debian 11 (Bullseye) shipped it.
set or read a window's WM_COLORMAP_WINDOWS property