CeCILL-B and the desert island test
The CeCILL-B license  includes the following wording in
Any Licensee who may distribute a Modified Software hereby
expressly agrees to: ... mention, on a freely accessible
website describing the Modified Software, at least
throughout the distribution term thereof, that it is based
on the Software licensed hereunder....
I believe this fails the desert island test, since it requires "a freely
accessibly website". Do you agree?
Is there a standardized procedure within Debian we could use to switch
packages in main from CeCILL-B to CeCILL-C? CeCILL-B says that
A Modified Software may be distributed under the CeCILL-C
license. In such a case the provisions set forth in
Article 5.3.4 shall be optional.
I believe even a trivial change to a CeCILL-B-licensed work would allow
distribution under CeCILL-C. I do not think CeCILL-C fails the desert
island test in the same way, and while CeCILL-C does contain a choice of
venue clause, past discussion here has illustrated precedent for Debian
accepting licenses with choice of venue clauses into main ( et seq.).