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slotLabelFormat

Determines the text that will be displayed within a time slot.

Date Formatter, default:

{
  hour: 'numeric',
  minute: '2-digit',
  omitZeroMinute: true,
  meridiem: 'short'
}

The default English value will produce times that look like 5pm and 5:30pm.

Timeline View

For Timeline view, one string can be given for creating a single header row, or an array of strings can be given to create multiple tiers of header rows.

slotLabelFormat: [
  { month: 'long', year: 'numeric' }, // top level of text
  { weekday: 'short' } // lower level of text
]

Timeline view is a premium feature.