It looks like you've disabled the loading of the wpDiscuz fontawesome CSS library.

Go to wpDiscuz > Settings > Styles and Colors enable it and check again please.

Before the check delete all caches if there are any.

I have the plugin installed on two sites, and the issue appears exactly the same on both sites. 

Example: https://www.hippieonholiday.com/advanced-keyword-research-training/

You can see that while all of the buttons work properly, the buttons:

-Hottest Comment Thread

-Most Reacted Comment

-My Content and Settings

-Stick this comment

-Close this thread

and

-Notify of new replies to this comment

All appear to be displaying quite strange. I've tried checking for plugin conflicts & deactivating my caching plugin (sg optimizer) but have had no luck. Any ideas? 

The buttons that are just for me (ie close this thread) don't really matter, but it would be nice for the buttons seen by readers to actually display without hovering. 

Thanks for any insight.