Adding CSS classes to custom buttons

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Feature Description

Continuation of https://github.com/fullcalendar/fullcalendar/issues/5117

It would be nice if we could add CSS classes to custom buttons. That way we can visually separate the buttons, which can make them more user friendly. For example, I’d like the “Today” button to be more prominent than the other buttons in the toolbar.

Something like this would already suffice:

customButtons: {
    dangerousButton: {
      text: 'dangerous action',
      classNames: 'btn-danger btn-sm',
      click: function() {
        alert('this will do something dangerous');
      }
    }
}

[stclairdaniel]

I’ll take it a step further - why not just allow passing in a component?

[jaapz]

Or a rendered dom tree, we’re not using React…