$ xwininfo -tree -root| grep "has no name"
     0xa800048 (has no name): ()  390x43+944+621  +944+621
     0xa80142e (has no name): ()  147x26+1056+66  +1056+66
     0xa80007a (has no name): ()  156x26+1275+356  +1275+356
     0x40000e (has no name): ()  1920x22+0+-22  +0+-22
     0x40000d (has no name): ()  1920x22+0+0  +0+0
     0x1800008 (has no name): ()  1x1+-1+-1  +-1+-1
     0xa801454 (has no name): ()  409x215+1006+773  +1006+773
     0x980000f (has no name): ()  1x1+-1+-1  +-1+-1
     0xa80138d (has no name): ()  140x26+707+837  +707+837
     0xb000001 (has no name): ()  1x1+0+0  +0+0
     0xa800005 (has no name): ()  1x1+0+0  +0+0
     0x9200004 (has no name): ()  1x1+0+0  +0+0
     0x8e00001 (has no name): ()  1x1+0+0  +0+0
     0x9000004 (has no name): ()  1x1+0+0  +0+0
     0x8400004 (has no name): ()  1x1+0+0  +0+0
     0x800001 (has no name): ()  10x10+-20+-20  +-20+-20