Is there a need for a confirmation button on a multi-select comboboxes?

Is there any reason we should include a confirmation button on our multi-select comboboxes? What are best practices for the design of these controls?

Mouse Functionality:

  • Clicking outside of the modal (clicking the glass) will exit the modal… (keeps selections)
  • Clicking the search icon opens/closes the modal… (keeps selections)

Keyboard Functionality:

  • Tabbing closes the modal… (keeps selections)
  • The escape key closes the modal… (keeps selections)
  • Enter selects/deselects items

Without Confirmation Button:

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With Confirmation Button:

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