Either Zholink couldn't parse images from the web page, or the web site intentionally prevents viewing those images when it's not viewed from their site.  If you're a web developer, you might also notice a bunch of browser console warnings such as "mixed content" or 401 errors.  Mixed content means that Zholink is loaded over HTTPS and the link is loaded by HTTP, which causes that warning.  The 401 errors occur because the site blocked images from being loaded by Zholink.