How to reproduce :

• create a new type of content with this filter

  <cms:metadata name="link-attachment" type="file">
  					<label i18n="true">CONTENT_KIOSQUE_ATTACHMENT</label>
  					<description i18n="true">CONTENT_KIOSQUE_ATTACHMENT_DESC</description>
  					<widget>edition.file</widget>
  					<widget-params>
  						<param name="filter">pdf</param>
  						<param name="allowSources">external,resource</param>
  					</widget-params>
  				</cms:metadata>

• In the version that I use, this filter is invalid,
• the content type that I created has some repeaters, when I click on add a new repeater, the repeater disapears