Make "Clear Selection" Button Appear in a Custom Widget

[intapiuser]

For this button to be shown, the widget must be configured to work as a "selector" widget, so make sure your custom widget plugin has the following items in its manifest:

- in the manifest's "data" object, a property defining which panels can be used as selectors (usually its just one panel):

selection: ['category']

- in the manifest's "options" object, selection is enabled:

selector: true