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To create a new custom summary page, you need to create a single XML file in your custom project's directory under ../pages/summary/<module_name>.
All custom summary pages should follow If the new summary page will be used to override system's release functionality, must follow this naming convention: <release_page_filename>Custom.xml. If not, it just has to have a unique file path.
In the following example, a new summary filter and field needs to be added to the existing contact information summary page. To do this, you have to copy release summary page contactInformation.xml in your custom projects directory under ../pages/summary/contactInfo, rename it to contactInformationCustom.xml and add the new summary filter and field.
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