/usr/share/xcrysden/images/xcMenuEntry_down.xbm is in xcrysden-data 1.5.53-1.
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 | #define ComboBox_down_width 11
#define ComboBox_down_height 14
static char ComboBox_down_bits[] = {
0x00,0x00,0x70,0x00,0x70,0x00,0x70,0x00,0x70,0x00,0x70,0x00,0xfe,0x03,0xfc,
0x01,0xf8,0x00,0x70,0x00,0x20,0x00,0x00,0x00,0xfe,0x03,0xfe,0x03};
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