When I open this page:
the correct code blocks (question and answer) flash up for a fraction of a second and then disappear, leaving a grey block.
I suspect that this has something to do with the jTab support for code blocks.
Trying to put the code in a
<pre></pre> wrapper didn't work for me;
I believe that it has to do with the use of
>> constructs (or maybe other special characters) in lilypond source.
Being able to correctly support lilypond syntax as code blocks will greatly improve questions about this software.
This question is related to Guitar tab plugin (jTab) should be active only in questions tagged [guitar] if the problem is with the application of the jTab parser.