You should only be seeing that particular layout on phone and tablets. Is this happening on your desktop? The desktop layout should have all links on the top in a navbar.
I’m using Firefox too on Windows 10 64bit Windows, and mine looks exactly like Blackgoku - Can you post if you’re using a specific screen resolution? Or if possible your user agent data? - I’m only getting that on on phones and tablets, on which it is quite nice
As @BlackGoku36 said above that seems to be a zoom issue. Going off the top of my head when I did the new site, the break from mobile view to desktop view is based off of viewport resolution,not explicitly os resolution. This makes it work the same independent of what you are using to view the site. However when you use a browsers zoom features that causes the browser to report a viewport resolution independent of your native os resolution. So right now the website is getting reported to that the veiwport is less than 960 across.