Safari 10 and later no longer support the method by which the NewsBlur Web app opens stories in new tabs. This extension gives NewsBlur the ability to do so again.
For Safari 10 and 11, download the extension from this site.
After installing the extension, reload the NewsBlur tab if it's open, or just quit and reopen Safari. You should then be able to use the 'o' or 'v' keys to open stories in new tabs.
If you have the NewsBlur Web app installed on your own server (i.e., if you do not access NewsBlur by going to newsblur.com), you can specify the domain of your own server in Safari’s Preferences. The extension will only work on this domain (and subdomains thereof). You will need to reload/reopen the site after changing this domain.
Safari 12 no longer supports extensions like this one. I am working on converting NewsBlur Open in New Tab into a Safari 12-compatible app extension. It behaves similarly, except preferences are now within the application, and unfortunately Safari no longer allows extensions to control tab ordering.
Enjoy!
Nicholas Riley