Before I waste more hours, could it be that in q2a v1.5.3 the following html validation problem is solved:
end tag for "DIV" omitted, but its declaration does not permit this
start tag was here: <DIV CLASS="qa-q-view-main">
See the validation of my site here: http://validator.w3.org/check?uri=http%3A%2F%2Fwww.gute-mathe-fragen.de%2F2450%2Foberflache-des-quaders-wenn-eine-seite-unbekannt-ist&charset=%28detect+automatically%29&doctype=Inline&group=0&verbose=1&user-agent=W3C_Validator%2F1.3
The FORM tag seems to be on the wrong position.
I ask because in my advanced theme I cannot find stuff that could be responsible for the break.
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