Comment 4 for bug 2032851

Had this when updating from ubuntu (with unity) 18.4 to 20.04 Yesterday (27 Aug)

Possible Work around?
Moved bf9d6da9.0 to desktop (Moved, just in case was not a solution as had tried re-namaing, with no effect)
sudo apt-get install -f, then ran ok.

afterwards noted that etc/../cache/ & desktop/bf9d6da9.0 no longer present on the system

NB - to do this had to use back version of Ubuntu, as new version did not load.