Hello, I had the same problem, I could not consult the update-manager details. I updated this two packages in unstable:
apt-get install -t unstable update-manager/unstable apt-listchanges/unstable and now I have the details of the update. I think the testing packages was buggy. Thanks to the maintener of this package. LGDN -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
