pub fn at_turn_end(cb: impl FnOnce() + 'static)Expand description
Run cb once, when the current turn settles: after the drain inside a drain or a batch
(even a batch that leaves no reactive work behind), or right away when no turn is open.
This is how a consumer coalesces a burst of changes into one pass. Swapping a page withdraws the old page’s toolbar items and contributes the new page’s within one turn, and only the settled result is worth handing to the toolkit.