XSetClassHint(3) on Linux
The text c7ece131d07c, as Debian 13 (Trixie) shipped it.
allocate class hints structure and set or read a window's WM_CLASS property
The text c7ece131d07c, as Debian 13 (Trixie) shipped it.
allocate class hints structure and set or read a window's WM_CLASS property