Comment 1 for bug 637176

This is not a bug, it's a deliberate change. Since this change was introduced, CDs kept overflowing and growing every day, and removing them again (and doing a couple of rebuild) has already saved us an order of 15 MB on the CDs (for question 1). As for (2), the intention is to not carry Ubuntu deltas, of course; it's not really that useful to ship upstream changelogs in the first place. If you want to make them easily accessible, you could put an URL to the upstream git etc. to the README.

This basically reflects the cdbs change from ages ago:

    - 1/rules/debhelper.mk.in:
      + Do not install upstream changelogs by default. They are huge and thus
        waste a lot of archive and CD space, quite uninteresting for ordinary
        users, and easy to get by downloading the source package or visiting the
        upstream page pointed out in copyright.