Heatmap Enable Legend Not Working Dynamically

[hrramirez]

Expected behaviour

Dynamically show and hide the legend by toggling between enabled: true and enabled: false

Actual behaviour

Dynamically showing/hiding the legend by toggling between enabled: true and enabled: false works
great on all other Highcharts charts. However, on a heatmap, even if the value for the legend is set to enabled: true the chart
will not dynamically show the legend. It will not expand and show the legend like all other charts.

Live demo with steps to reproduce

To reproduce on a heat map:

• Toggle the Update Legend button: https://jsfiddle.net/yesg2xc1/
• Notice it will dynamically hide the legend, but it won't dynamically show it again. You can check the console to verify that the enabled option is being toggled.
• The expected behavior with the same implementation on a bar chart: https://jsfiddle.net/x8fkdoyj/1/

Product version

Affected browser(s)