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I am solving all my warnings/errors in my document. I have solved everything except for 2:
Underfull \vbox (badness 6876) has occurred while \output is active 
Underfull \vbox (Badness 2142) has occurred while \output is active 
My first question:
How can I found out where this error occurs? Is  and  the pagenumber? I cannot find anything strage there.
How can I get more information where error occurs? Is there a debug option (like for overfull).
I found already this question: with debug option:
But that did not help.
How to deal with this?