A routine upgrade of testing this morning introduced something that propagates the behaviour observed in these bugs in testing : pages trying to display audio or video media fail, with "error code : 256".
Someone calling himself fjhc on IRC #debian-next pointed me to #963080, and I thought useful to point the need for a somewhat urgent workaround : testing is used by a lot of people (much more than unstable). Of note : Google's chrome (.deb package downloaded from their site a while ago) is immune. HTH, -- Emmanuel Charpentier