I've brought libmatroska back into shape in our GIT repository. It is
currently targeted at experimental, because it needs libebml from
there. Alternatively, if libebml is uploaded to unstable before, I
think libmatroska could go there as well.
Both libraries bump SONAME, but the transition will be marginal, since
no other packages (build-) depend on libmatroska than mkvtoolnix and
vlc (and additionally libmatroska depends on libebml, of course).
Feel free to upload!
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