The widget expand a recurrence event based on its recurrence rule value. If there are exceptions, it will check whether the generated occurrence can be found in it the list. If it can, then the occurrence will not be rendered. This is how the widget will leave an empty slot for deleted occurrences or for exceptions events.
The recurrence exception value should match the RFC5545 standard:
If the dates are sent in the correct format, the widget will display them correctly. Check this Dojo demo built based on the given details:
Please note that "title" field is mandatory.
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