After a recent update of TW I see a broken layout with nvim in diff mode (-d)
when a scroll down. I attach a screenshot before and after CTRL-L.

I tested that this is broken:
$ env | grep TERM
COLORTERM=1
TERM=xterm-256color

If I test this:
$ TERM=xterm /usr/bin/nvim -d 

it's broken. But TERM=linux is fine. I'm using gnome-terminal, but I see the
same in KDE konsole. Note that vim is fine and I've also tried to build a bit
older nvim release and it's also broken on the TW.