/usr/include/X11/bitmaps/icon is in xbitmaps 1.1.1-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 | #define icon_width 16
#define icon_height 16
static char icon_bits[] = {
0xff, 0xff, 0xab, 0xaa, 0x55, 0xd5, 0xab, 0xaa, 0x05, 0xd0, 0x0b, 0xa0,
0x05, 0xd0, 0x0b, 0xa0, 0x05, 0xd0, 0x0b, 0xa0, 0x05, 0xd0, 0x0b, 0xa0,
0x55, 0xd5, 0xab, 0xaa, 0x55, 0xd5, 0xff, 0xff};
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