Function animating_leaves 

pub fn animating_leaves(root: &dyn Widget) -> Vec<String>

Paths to the deepest widgets under root asking for animation frames: the ones actually holding the loop open, not every container above them, each with its box and crate::widget::Widget::animation_detail. ~ marks a widget that animates without asking to be redrawn: a retained parent cache then never reaches it again. Allocates, so only diagnostics call it.