The item is a Safari browser screen image, from what version OS X and which Safari build?
The short term would be to use another browser, such as Mozilla Firefox. The link and associated files
as far as I went (from site URL in your screenshot) -- all worked OK without issue. Safari is second or
third of three browsers I use in my newest model Mac. (And I've several different Macs + OS X.)
If you already have Firefox, then test to see what renders differently. Does your Safari have a Developer
custom item in its menu bar and if so have you selected anything extra-ordinary from there lately?
• How to Download & Install Firefox on Mac - Mozilla Firefox Help:
https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac
The rendering of the page looks rather like a Console utility log file instead of the web page content.
-- If you downloaded a file and somehow got Console to open it, that's what it would look like.--
Not sure what to check in Safari to make it revert to a normal view. A developer setting could make it
render pages in a different way; but I've never seen one quite like that in regular browser view.
A browser can allow you to use different views to access content; to see and modify code. If you
write any HTML or edit, a word processor like TexEdit or
barebones.com/products/textwrangler/
you'd be familiar with alternative page views. Most of my browsers can render pages like that.
Sorry to not be of much help. If you need to see the page, and can use or get another browser,
that is a quicker way to do so. A 'web developer' option in Safari may render pages that way.
Good luck! 🙂