404 to .svg file from Jakub Steiner (Jimmac)

I keep seeing the below pop up in my logs. It's for artwork from Jakub Steiner, an artist who created a lot of gnome artwork (icons, etc.).

Sender: gnome-software
Message: not handling error download-failed for action refine: failed to download http://people.gnome.org/~jimmac/gnome-software/slack-logo.svg: Not Found: <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>404 Not Found</title>
</head><body>
<h1>Not Found</h1>
<p>The requested URL was not found on this server.</p>
</body></html>

That URL is a Red Hat Enterprise Linux Test Page that's gone 404.

Using:
sudo grep -rnw '/' -e 'http://people.gnome.org/~jimmac/gnome-software/slack-logo.svg'
... to search files for that text string, I find a lot of /var/log/syslog and /var/log/auth.log entries.

They may have set permissions so that it isn't downloadable. If it opens in the browser, but doesn't through another method, they may have disallowed that option.

It doesn't open in the browser, either. It's 404.

This is associated with gnome-software. In the same sub-list with that error is:
Sender: gnome-software
Message: CSS parse error 1:107: Using one color stop with linear-gradient() is deprecated.