Example that fails using Change I2fa8802e

getConfigurationFor.php

<?php
	public function getConfigurationFor($propertyName) {
		if (isset($this->subConfigurationForProperty[$propertyName])) {
			return $this->subConfigurationForProperty[$propertyName];
		} elseif (isset($this->subConfigurationForProperty[self::PROPERTY_PATH_PLACEHOLDER])) {
			return $this->subConfigurationForProperty[self::PROPERTY_PATH_PLACEHOLDER];
		}

		return new \TYPO3\FLOW3\Property\PropertyMappingConfiguration();
	}
?>

gistfile1.txt

$pMC->allowCreationForSubProperty('items.*');
$pMC->forProperty('items.*')->setTypeConverterOption(
'TYPO3\FLOW3\Property\TypeConverter\PersistentObjectConverter',
\TYPO3\FLOW3\Property\TypeConverter\PersistentObjectConverter::CONFIGURATION_OVERRIDE_TARGET_TYPE_ALLOWED, TRUE);

And in a template have
<f:form.textfield property="items.0.__type" value="\My\Package\Domain\Model\SomeClass"/>
(imagine this to be only the first row, and the rest being autogenerated using javascript when the use hits a "add more" button ...)

Not the best example maybe, but it's short and obvious and in fact I have such a case where items is a collection of objects that can vary in type
and so in the template I have to set the concrete type like seen above
@var \Doctrine\Common\Collections\Collection<\My\Package\Domain\Model\AbstractClass>

Short explanation for the problem:
==================================
On pulling the configuration for items.0.__type, first the configuration for "items" will be pulled, then its subconfiguration for "0" 
(which has been automatically generated by the renderTrustedFields & co functionality), then its subconfiguration for "__type"

Here comes the problem, the automatic generated configuration gets in our way. We want our rules to be used, 
the one that we declared in our controller maybe, but because "0" is more specific than "*", 
the "0" path-configuration will be used instead !!! and all its subconfigurations, and none of the "*.xyz" configurations.

Now one could just add a specific exceptional rule in the controller to handle this one specific problem above. 
But this becomes impossible if you have a path as complex as this... chapters.*.parts.*.cards.*.sides.*.answers.*.stringVersions.* 
and not only 0 but always 0,1 and 2 as fixed rows in your templates.