Steps to reproduce the issue

1. Create a space with more than 10100 pages.
2. Go the page "Space Admin >> Content Tools >> Export"
3. Select "PDF" then "Custom Export"
4. Click the button "Deselect All" to uncheck all box.
5. Select a couple page in the tree then export to PDF.

Expected behavior

Confluence should export only those selected pages.

Current behavior

Confluence is exporting almost the entire space.

Workaround solution

1. Run the following query to identify the biggest spaces without your Confluence instance:

   select s.SPACEKEY,count(c.CONTENTID) from CONTENT c join SPACES s on c.SPACEID=s.SPACEID where c.CONTENTTYPE='PAGE' and c.PREVVER is NULL and c.CONTENT_STATUS='current' and s.SPACETYPE='global' group by s.SPACEKEY order by count(c.CONTENTID) desc;
   

2. Add the parameter "maxParameterCount" with the biggest number of pages (please make the value bigger to have some reserve) in the connector configuration on the file server.xml, for example:

           <Connector port="8090" connectionTimeout="20000" redirectPort="8443"
                   maxThreads="48" minSpareThreads="10"
                   enableLookups="false" acceptCount="10" debug="0" URIEncoding="UTF-8"
                   protocol="org.apache.coyote.http11.Http11NioProtocol" maxParameterCount="18000" />
   

3. Restart Confluence and try to export the pages again.