bug#2343: Color highlighting leaves a trail of cursors on the screen

[David De La Harpe Golden]

Chong Yidong wrote:
> Kim Rose Carlsen <KRC@fullrate.dk> wrote:

> > Tested with terminal:
> > Gnome-terminal (term=xterm || term=linux)
> > xfce-terminal  (term=xterm || term=linux)
> > rox-terminal   (term=xterm || term=linux)

All those use the libvte terminal emulator widget underneath.
It _may_ be some issue with that rather than emacs, there is an 
unconfirmed bug report of various redraw issues in recent vte
when cursor positioning is used:
http://bugzilla.gnome.org/show_bug.cgi?id=528077


> > Cannot reproduce with 
> > linux console (term=linux || term=xterm)
> > xterm (term=xterm || term=linux)
>
> I'm pretty baffled by this one.  I can reproduce it using
> gnome-terminal, and a slightly different version of the bug seems to
> show up in Emacs 22 too.  Anyone have any idea?

I can reproduce something like it with xfce4-terminal with

emacs -nw -Q

Without -Q, I have my usual non-default dark blue background set on my 
default face in emacs, and then the block artifact doesn't appear,
so maybe there's some place (whether in emacs or the vte widget I don't 
know) where a background redraw is being skipped when it shouldn't be,
probably as an optimisation for the terminal-default background case.