When sending an event with a boolean property that can have the value of true or false, the property is shown when there is true value on the property and is not shown when it’s false.
For instance, I have an event called ‘Test event’ and a db property test_property that has a boolean value (true or false).

$this->mixPanelClient->track("Test event", ['Test property' => is_null($test_property) ?: false]);

Unit testing is working in a case when test_property is false, but when I go to Mixpanel Live view and check the event the property is not there. It only shows it when it is true.