I disabled all extensions and the FCKeditor
worked. I reactivated the extensions step by step and found out that
there is a conflict with the semantic mediawiki extension. How can I
make sure that both are working properly? Is there a way that the
FCKeditor and the semantic mediawiki can use different hooks?
I had a quick look on the sourcecode of the semantic mediawiki (current
version). The semantic mediawiki and the FCKeditor extension use one
parser hook in common which in itself is no problem.
However, there are more hook calls involved and here we are all in all
in trouble as FCKeditor extension bypasses the parser and the semantic
mediawiki uses parser hooks for modifying the output text.
Your initial problem was that you did not see any output text when using
both extensions. Here I am still lost. Although the extensions cannot
work correctly you should see at least something. Provided that this
issue could be solved, it might be possible to adapt the FCKeditor
extension in such a way that both extension can coexists - at least
until the next software update. Hence, sooner or later you will be
again in trouble.
Sorry, there is no easy solution to your problem Markus