Issue Summary

Exporting large pages to PDF leads to StackOverflowError even after setting high memory for stack size.

There is no proper pattern as to how large the page should be which will eventually lead to the error when exported to PDF.

Steps to Reproduce

1. Increase the stack size to 100 MB (as an example)

   CATALINA_OPTS="-Dconversion.sandbox.stack.limit.megabytes=100 ${CATALINA_OPTS}" 

1. Create a large page with 1000+ lines (as an example)
2. Export the page to PDF.

Expected Results

• It is expected that the PDF export of the page completes successfully

Actual Results

• PDF export leads to error - StackOverflowError

  2024-02-13 10:53:04,164 ERROR [http-nio-8090-exec-3 url: /confluence/500page.jsp; user: admin] [atlassian.confluence.status.SystemErrorInformationLogger] logException Unhandled exception 5e1dd2bf-75a0-4512-8952-c9815ae1d012: Method \"execute\" failed for object com.atlassian.confluence.extra.flyingpdf.impl.ExportPageAsPdfAction@744cb65f
   -- traceId: 0b1b919166770a56
  ognl.MethodFailedException: Method "execute" failed for object com.atlassian.confluence.extra.flyingpdf.impl.ExportPageAsPdfAction@744cb65f [java.lang.StackOverflowError]
  Caused by: java.lang.StackOverflowError
          at java.base/java.io.ObjectOutputStream.writeClassDesc(ObjectOutputStream.java:1217)
          at java.base/java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1418)
          at java.base/java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1169)
          at java.base/java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1543)
          at java.base/java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1500)
          at java.base/java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1423)
          at java.base/java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1169)
          at java.base/java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1543) 

Workaround

We need to delete the data from the page and then export the page to PDF. As mentioned earlier, there is no fixed pattern of how much data (number of lines) to be retained on the page, we should follow a trial and error approach.