Package: release-notes 4.2 "Checking system status" says:
The upgrade process described in this chapter has been designed for upgrades from “pure” wheezy systems without third-party packages. For the greatest reliability of the upgrade process, you may wish to remove third-party packages from your system before you begin upgrading. However it does not say how to find such packages on one's system. There are probably many ways to do this, but an easy one is to install the apt-forktracer package and just run apt-forktracer. It will list those installed packages: - which are not available from an official Debian repository, or - whose installed version is more recent than the one in an official Debian repository which I think is a good approximation of the packages mentioned in that section. Example output on a wheezy system which shows some non-Debian packages, and locally patched packages. porridge@butla:~$ apt-forktracer | sort adobereader-enu (9.5.5) # bambam (0.5+dfsg-0.1) command-runner-applet (0.3-1) [Debian: 0.2-2] exiftran (2.07-10.1) [Debian: 2.07-10+b1] google-chrome-stable (42.0.2311.152-1) [Google, Inc.: 42.0.2311.152-1] how-can-i-help (7~bpo70+1) skype (4.3.0.37-1) xscreensaver-data (5.15-3.1) [Debian: 5.15-3] xscreensaver-gl (5.15-3.1) [Debian: 5.15-3] xscreensaver (5.15-3.1) [Debian: 5.15-3] porridge@butla:~$ It may be too late to change this for jessie, but please consider adding this info for stretch. -- Marcin Owsiany <mar...@owsiany.pl> http://marcin.owsiany.pl/ GnuPG: 1024D/60F41216 FE67 DA2D 0ACA FC5E 3F75 D6F6 3A0D 8AA0 60F4 1216 "Every program in development at MIT expands until it can read mail." -- Unknown
