chart zoom.buttons is {value}, which is not ...

Warnings reference › chart:zoom:buttons:*

Identifier

chart:zoom:buttons:*

Raised by

Charts

Since

1.72.0

What happened

A chart's zoom.buttons named something other than hover, always or none, so it could not say when the toolbar appears. The toolbar was built with the default behaviour rather than left out, which would have read as the whole option being broken.

The fix

Use buttons: 'hover' (the default), 'always' to pin the strip open, or 'none' to keep the zoom and drive it from your own controls.

The smallest fix

createChart({ grid, container, type: 'line', zoom: { buttons: 'always' } });

Reference

Covered in full at the API reference.