Combo buttons are preferred when more than one action is associated with a button. The primary action is visible and available on the button itself, while the secondary actions are accessed through the drop-down menu.
Combo buttons are created using Dijit's dijit/form/ComboButton and secondary actions are defined inside dijit/DropDownMenu using dijit/MenuItems.
This component is most easily implemented by programmatically instantiating mojo/widgets/ButtonGroup and passing a template string.
Be mindful of accessibility and tap sizes. Use semantic markup and keep in mind this pattern works best with 3 to 5 items.
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