[Bug 2130273] Re: do-release-upgrade deletes sources.list format entries during update to 25.10

[Launchpad Bug Tracker]

This bug was fixed in the package ubuntu-release-upgrader - 1:26.04.5

---------------
ubuntu-release-upgrader (1:26.04.5) resolute; urgency=medium

  * DistUpgrade: keep a disabled copy of .list files that could not be migrated
    (LP: #2130273)
  * DistUpgradeFetcherCore: use gpgv to verify signatures
    (LP: #2125687)
  * DistUpgrade: refuse to upgrade without unified cgroupv2 hierarchy
  * Run pre-build.sh: updating mirrors and translations.

 -- Nick Rosbrook <enr0n at ubuntu.com>  Wed, 28 Jan 2026 08:18:55 -0500

** Changed in: ubuntu-release-upgrader (Ubuntu)
       Status: Triaged => Fix Released

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to python-apt in Ubuntu.
https://bugs.launchpad.net/bugs/2130273

Title:
  do-release-upgrade deletes sources.list format entries during update
  to 25.10

Status in python-apt package in Ubuntu:
  Confirmed
Status in ubuntu-release-upgrader package in Ubuntu:
  Fix Released
Status in python-apt source package in Questing:
  New
Status in ubuntu-release-upgrader source package in Questing:
  New

Bug description:
  To reproduce:
  1. On Ubuntu 25.04, add a repository in the old sources.list format (https://wiki.debian.org/SourcesList#sources.list_format). For example, I've added the Mozilla Firefox repo via following https://support.mozilla.org/en-US/kb/install-firefox-linux "For Debian Bookworm or older" instructions.
  2. Start upgrade process to 25.10 via do-release-upgrade. In the beginning of the process, the sources.list format repos will be moved into e.g. "mozilla.list.migrate", while the deb822 repos will be copied into e.g. "ubuntu.sources.distUpgrade" 
  3. Finish upgrade. All files with deb822 format will still be there, but mozilla.list will be gone entirely.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/python-apt/+bug/2130273/+subscriptions