I’m using this package.

https://github.com/Malabarba/smart-mode-line

On Jun 12, 2016, at 2:50 PM, Alan Third <alan@idiocy.org> wrote:

On Sun, Jun 12, 2016 at 10:53:06PM +0300, Eli Zaretskii wrote:
From: James Nguyen <ja.nguyen@gmail.com>
Date: Sun, 12 Jun 2016 11:03:50 -0700

https://dl.dropboxusercontent.com/u/11400324/numberbug.mov

I cannot play this.  Any chance to get some more popular format?  An
image is enough, no need for a movie.

I've attached a screenshot from the movie. It looks like there's some
custom modeline stuff going on that draws the line-number at the
extreme left. If the number gets large enough it overflows into the
fringe where it's then left because that particular part rarely gets
redrawn.

It looks to me like there are two problems:

1. Whatever is writing the number shouldn't be trying to draw that
   far left.

2. That part of the screen shouldn't be writable. I recently fixed a
   problem with the cursor intruding into the fringe. I expect this
   is similar.

I'll have a look into number 2, but I don't know where to start with
number 1.
--
Alan Third
<Screen Shot 2016-06-12 at 22.39.48.png>