1. AIV application has different kind of charts to display data, when the user will enable legend in the widgets, the legend will look same like the chart type.
For example the chart is made of columns the legend will look like column, if chart is made of bars the legend will look like the bars.
now if user wants to eliminate this functionality then they can disable the Default markers, In AIV default markers are enabled by default,
that’s why the toggle button of default marker stays true in nature.

2. Example when Default marker enabled:

3. Example when Default marker disabled: