I have a triple-booter - Win7; Arch; Void and Void has GRUB installed to control the booting.
With os-prober at 1.70_1 if I run "xbps-reconfigure -f linux4.1" I only get Void in the GRUB menu.
If I downgrade to 1.67_1 I get all three as expected.
Not sure if this is a config issue somewhere (although I'm pretty vanilla locally) or an os-prober issue upstream.
I'm not mounting Win7 or Arch in Void if that makes a difference.