Cutting off one or both pigtails is another, often mean thing to do with pigtails. Often done by someone else as a prank or revenge, but also sometimes done by herself or himself for one reason or another. More movies coming soon.
Pic 1 showing an Indian teen boy in “Into the West (2005)” (episode 5) cutting off his pigtails with a knife. I think also other young men in long and rather thin pigtails. Setting in the 1870s.
Pic 2 is from “Problem Child”. A girl cutting off one pigtail from another girl. Scene at 51 minutes.
Another thing is dipping a pigtail in an inkwell at school from a boy behind. Is there any movie about that? Should be in LHOTP but I haven’t found it yet.