customize filter datalist : datepicker

Hello I am creating a plugin to personalize the search filter of a datalist I deployed my plugin in joget server but when I choose it to configure the input the screen freezes without having errors 

if you choose this plugin the screen stays like this : 

Java class : 

public class FieldDataListFilterType extends DataListFilterTypeDefault implements PwaOfflineResources {

public String getName() {
return "Field Data List Filter Type2";
}

public String getVersion() {
return "5.0.0";
}

public String getDescription() {
return "Data List Filter Type2 - Field";
}

public String getLabel() {
return "Date";
}

public String getClassName() {
return this.getClass().getName();
}

public String getPropertyOptions() {
return AppUtil.readPluginResource(getClass().getName(), "/properties/datalist/fieldDataListFilterType.json", null, true, null);
}

public String getTemplate(DataList datalist, String name, String label) {
PluginManager pluginManager = (PluginManager) AppUtil.getApplicationContext().getBean("pluginManager");
Map dataModel = new HashMap();
dataModel.put("name", datalist.getDataListEncodedParamName(DataList.PARAMETER_FILTER_PREFIX+name));
dataModel.put("label", label);
dataModel.put("value", getValue(datalist, name, getPropertyString("defaultValue")));
dataModel.put("contextPath", WorkflowUtil.getHttpServletRequest().getContextPath());
return pluginManager.getPluginFreeMarkerTemplate(dataModel, getClassName(), "/ressources/templates/datePicker.ftl", null);
}

public DataListFilterQueryObject getQueryObject(DataList datalist, String name) {
DataListFilterQueryObject queryObject = new DataListFilterQueryObject();
String value = getValue(datalist, name, getPropertyString("defaultValue"));
if (datalist != null && datalist.getBinder() != null && value != null && !value.isEmpty()) {
String cname = datalist.getBinder().getColumnName(name);

//support aggregate function
if (cname.toLowerCase().contains("count(")
|| cname.toLowerCase().contains("sum(")
|| cname.toLowerCase().contains("avg(")
|| cname.toLowerCase().contains("min(")
|| cname.toLowerCase().contains("max(")) {
queryObject.setQuery(cname + " = ?");
queryObject.setValues(new String[]{value});
} else {
queryObject.setQuery("lower(" + cname + ") like lower(?)");
queryObject.setValues(new String[]{'%' + value + '%'});
}

return queryObject;
}
return null;
}

@Override
public Set<String> getOfflineStaticResources() {
Set<String> urls = new HashSet<String>();
String contextPath = AppUtil.getRequestContextPath();
urls.add(contextPath + "/plugin/org.joget.apps.datalist.lib.TextFieldDataListFilterType/js/jquery.placeholder.min.js");

return urls;
}

fieldDataListFilterType.json: 

[{
title:'@@datalist.tfdlft.config@@',
properties:[
{
name:'defaultValue',
label:'@@datalist.tfdlft.defaultValue@@',
type:'datepicker'
}

]
}
]