While simple cases for leaders with leader-pattern="use-content" work there are a few more difficult to attack gremlins left.
When it comes to Knuth line breaking leaders are modelled as non breaking elastic glue. This allows for leaders under justification to fill the remaining space and works fine. However lets take this example: <fo:block> <fo:leader font-size="24pt" leader-pattern="use-content">x</fo:leader> The rest of the line </fo:block> Because the leader just becomes a piece of Knuth glue the Line LM doesn't know that it is actually a "24pt" font and doesn't calculate the line height correctly. Of course this is 'getting worse' when one thinks that the leader could contain nested inlines of different sizes/alignment/baselines/... All this information which is in some form or another normally used by the Line LM to calculate the line height and by the inline LMs to perform vertical alignments is not used. Don't think this is urgent and there is a disabled test case now for it. Are there other cases where we could have similar problems, i.e. the Knuth sequences not carrying all the information expected because some substitution is done - page number citations, markers, ....? Manuel
