T441

An entity extends only along a chart-space axis. A viewport-positioned line, box, or arrow has no chart axis and takes only null or extend.none. A top- or bottom-anchored pool pins the y axis, so extend.up, extend.down and extend.vertical are rejected there; a left- or right-anchored pool pins the x axis, so extend.left, extend.right and extend.both are rejected there. Move the entity to a pool whose free axis matches the extend direction, or drop the extend.

Failing example

script "conf"
data chart = subscribe(data.ohlcv)
state boxes = entities.boxPool(max: 2, anchor: anchor.topLeft)
on chart.update { boxes.get("b").set(8.0, 8.0, 40.0, 40.0, extend: extend.right) }

Corrected example

script "fixed"
data chart = subscribe(data.ohlcv)
state boxes = entities.boxPool(max: 2, anchor: anchor.topLeft)
on chart.update { boxes.get("b").set(8.0, 8.0, 40.0, 40.0, extend: extend.none) }