Problem "resolved" (for some value of "resolved") but leaving this here for context and reference.
No further help needed, but thoughts and comments welcome ...
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Last night I was installing pandoc, which went well enough, but then I needed \( \LaTeX\) so I did this:
$ sudo apt install texlive-full
All went well, until it got to here:
"Pregenerating ConTeXt MarkIV format. This may take some time... "
I let that run overnight, but finally killed it. It advised me to run this:
$ sudo dpkg --configure -a
So I did that, and once again it hung.
I killed the right sub-process and the remainder completed.
However ...
This morning I've been informed I have an update for vim. So I confirmed that, and now it's stuck again:
"Pregenerating ConTeXt MarkIV format. This may take some time... "
Help?


