The Presence model validation accepts an empty space as valid input. This should probably protect against a user entering an empty space to bypass validation. We put in this override

Ext.define('Ext.overrides.PresenceValidator',{

override: 'Ext.data.validator.Presence',

validate: function(value) {

var valid = !(value === undefined || value === null);

if (valid && !this.getAllowEmpty()) {

valid = !(value === '' || (Ext.isString(value) && Ext.String.trim(value) === ''));

}

return valid ? true : this.getMessage();

}

});