Neovim Colours

So I like neovim a lot.  But it has a few warts.  The most recent one was getting correct colour to work properly when sshed into a remote host.

So the obvious question was the TERM environment variable. Various changes pretty much had no affect.
So I tried google. This led me to this wonderful hack:

export NVIM_TUI_ENABLE_TRUE_COLOR=1

That worked... poorly. As in in it totally broke the color support entirely. I had black text on black.
Okay... search again: Lets search for that variable.
Bingo: neovim/src/tui/tui.c

A quick scan, and I see that the magic to enable 256 colours is:

• COLORTERM is set (to anything, eg "COLORTERM=nope")
• TERM is either xterm or screen