Hello Apache Struts Team.
There is an issue with the Struts include tag (s:include) when processing includes on a page that isn't using UTF-8 encoding (e.g. ISO-8859-1 or Windows-1252 page encoding).
In some circumstances the s:include tag results in truncated content from the child page (i.e. the parent page including the child page via s:include experiences incomplete rendering of the included content). This happens when the included page contains certain characters (e.g. 'ç') in a non-UTF8 encoding (whether directly or from a resource bundle).
There are no warnings produced in the logs (even in debug mode), so the issue can only be detected visually when things fail.
Changing all the content to UTF-8 is a workaround, but that is not feasible in all circumstances. Given the preceding and the lack of warnings I'm initially submitting it as a major priority.
I will attempt to submit a bugfix for consideration shortly.