something wrong with e.g. http://packages.debian.org/sid/i386/libprotobuf3/download

[Samuel Bronson]

Several parts of the page at
http://packages.debian.org/sid/i386/libprotobuf3/download are empty in such
a way as to confuse and/or befuddle those who might somehow reach it.
Missing dummy text in the suggested line for /etc/apt/sources.list,
missing/empty list of mirrors (rather than explicitly stating that there are
no mirrors), etc. (Presumably there are many other such URLs.)