I've been using vi for years, I know there's other/better editors, but, I prefer to stick to what I'm used to.
After recent upgrade of my GFN from Jessie -> Stretch, vi/vim started to behave oddly. In particular on serial console vi became "mouse aware", making it difficult to copy and paste from outside the console, and instead of a screen of white text on black, I have a screen full of a very dark color on black making it virtually unreadable.
It seems that "syntax highlighting" and "mouse" had been turned on. After quite a while googling I figured out how to revert to pre-Stretch vim behaviour, which is a simple comment out of :
let g:skip_defaults_vim = 1
in the /etc/vim/vimrc file
which I gathered from here -
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=864074
BR
Don Charisma ... because anything is possible with Charisma
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