Snog's OS detector...

On the sidebar right under my username and avatar it says I use Linux and Chrome, why does it not say Ubuntu like the other Ubuntu users I see?

I am on Ubuntu 19.04. I was just curious.

I would have to see your user agent string to be able to answer that.
https://www.whatsmyua.info/But I would bet it looks similar to this...
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.131

Which if it does, your system isn't identifying itself as Ubuntu, it's just identifying itself as generic Linux.

If it were it would look similar to mine...
Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:66.0) Gecko/20100101 Firefox/66.0

Which if I switch to Chrome, it results in this user agent...

Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36

And that changes my OS and Browser designations to correctly match the user agent supplied. A generic Linux with the Chrome browser.