Validation error with different result in PF 11 and PF 14

[AndrewChurchill1970]

Hello.
Problem: After validation failed the bean value is not shown anymore in p:dialog.
steps: open dialog, default value of bean is shown, delete content of inputfield, press OK, validation error caused, press cancel, open dialog again => no bean value shown in inputfield (in PF 11 the bean value has been shown)

xhtml-page:

<h:head>
<title>PF Validation Problem</title>
</h:head>

<h:body id="body">
<h:form id="baseForm">

<p:commandButton process="@this" title="open dialog" update="carId" onclick="PF('dlgIdWidget').show();" />

	<p:dialog id="dlgId" widgetVar="dlgIdWidget" header="Test- dialog" modal="true" closeOnEscape="true">
		<p></p>
		<p:outputLabel value="Car: " for="@next" />
		<p:inputText id="carId" value="#{testView.car}" required="true" />
		<p></p>
		<p:commandButton id="cancelId" value="Cancel" 
			action="#{testView.pbCancel()}" 
			onclick="PF('dlgIdWidget').hide(); return false;" 
			process="@this" immediate="true" ajax="false" icon="pi pi-times" />
		<p:commandButton id="saveId" value="OK" 
			action="#{testView.pbOK()}" update="@none" process="@this dlgId" icon="pi pi-save" />
		<p></p>
		<p:messages>
			<p:autoUpdate />
		</p:messages>
		<p:growl>
			<p:autoUpdate />
		</p:growl>
	</p:dialog>

</h:form>

</h:body>

bean:
public class TestView implements Serializable
{
private static final long serialVersionUID = 4290918565613185179L;
private String car = new String();

@PostConstruct
public void initializeView()
{
	car = "LADA TAIGA";
	System.out.println("initializeView() => car: " + car);
}
public void pbOK()
{
	System.out.println("pbOK() => car: " + car);
}
public void pbCancel()
{
	System.out.println("pbCancel() => car: " + car);
}
public String getCar()
{
	return car;

public void setCar(String car)
{
	this.car = car;
}

}

web.xml:

primefaces.RESET_VALUES
false

What we tried:
if we use return true instead of return false in onclick() =>
onclick="PF('dlgIdWidget').hide(); return true;"

it works with some sideeffects:

• if you use closeable of p:dialog the content of bean will not be shown after starting the dialog again
• after closing p:dialog the view is rendering the view content again (e.g. displaying content of datatable)
• closeable never works correct if validation fails (doesn't matter if true or false will be returned)

INFO:
In PF 11 it works in both cases (true or false for that parameter) =>
primefaces.RESET_VALUES

Has anyone an idea or a solution for our problem?