I have made some progress. Although apt has never reported any broken packages smanyare listed in apt.log
cat /var/log/dist-upgrade/apt.log | grep Broken sudo apt-get purge opencv libblas3 libopenblas-base Reading state information... Done The following packages will be REMOVED blender-data dleyna-renderer freepats gimp-data gir1.2-gtk-2.0 gstreamer1.0-plugins-bad-faad gstreamer1.0-plugins-bad-videoparsers libamd2.4.1 libavcodec-dev libavformat-dev libavresample-ffmpeg2 libavutil-dev libbabl-0.1-0 libblas-common libboost-locale1.58.0 libcamd2.4.1 libccolamd2.9.1 libdc1394-22-dev libde265-0 libflite1 libfluidsynth1 libgimp2.0 libgstreamer-plugins-bad1.0-0 libgtk2.0-dev libgtkglext1 libilmbase-dev libjasper-dev libjemalloc1 libmimic0 libmjpegutils-2.1-0 libmpeg2encpp-2.1-0 libmplex2-2.1-0 libofa0 libopencolorio1v5 libopenexr-dev libpangox-1.0-0 libsodium18 libsoundtouch1 libspandsp2 libspnav0 libsrtp0 libswresample-dev libswscale-dev libtbb2 libtinyxml2.6.2v5 libwildmidi-config libwildmidi1 libyaml-cpp0.3v5 libzbar0 libzmq5 opencv-data python-opengl python-qt4 python-qt4-gl python-sip 0 to upgrade, 0 to newly install, 55 to remove and 0 not to upgrade. After this operation, 270 MB disk space will be freed. Do you want to continue? [Y/n] y sudo apt-get autoremove $ sudo apt-get autoremove Reading package lists... Done Building dependency tree Reading state information... Done The following packages will be REMOVED blender-data dleyna-renderer freepats gimp-data gir1.2-gtk-2.0 gstreamer1.0-plugins-bad-faad gstreamer1.0-plugins-bad-videoparsers libamd2.4.1 libavcodec-dev libavformat-dev libavresample-ffmpeg2 libavutil-dev libbabl-0.1-0 libblas-common libboost-locale1.58.0 libcamd2.4.1 libccolamd2.9.1 libdc1394-22-dev libde265-0 libflite1 libfluidsynth1 libgimp2.0 libgstreamer-plugins-bad1.0-0 libgtk2.0-dev libgtkglext1 libilmbase-dev libjasper-dev libjemalloc1 libmimic0 libmjpegutils-2.1-0 libmpeg2encpp-2.1-0 libmplex2-2.1-0 libofa0 libopencolorio1v5 libopenexr-dev libpangox-1.0-0 libsodium18 libsoundtouch1 libspandsp2 libspnav0 libsrtp0 libswresample-dev libswscale-dev libtbb2 libtinyxml2.6.2v5 libwildmidi-config libwildmidi1 libyaml-cpp0.3v5 libzbar0 libzmq5 opencv-data python-opengl python-qt4 python-qt4-gl python-sip 0 to upgrade, 0 to newly install, 55 to remove and 0 not to upgrade. After this operation, 270 MB disk space will be freed. Do you want to continue? [Y/n] y The upgrade now proceeds to the next stage and completes. It seems autoremove is more critical than I imagined. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1811203 Title: improve diagnostics and advice for "could not determine the upgrade" errors. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1811203/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
