Do you mean the color scheme? It’s called Monokai, and I think it’s widely available among text editors.
Codepen doesn’t do it for you? I find it really easy to do these little challenges and you will use it later on anyway.
If you want to be able to run things locally, you can use something like Atom, GitHub’s text editor. With the HTML preview option it’s fine for web development, and I use a terminal add-on (terminal-plus I think) to run test code that doesn’t use HTML.
If you don’t want to be fussy about that all that and just need JavaScript or JavaScript libraries (especially React), just use CodePen if you are learning. Trying to set up a local React environment can be truly brutal.
Other options instead of CodePen include JSfiddle and JSbin. All three allow you to register accounts and save projects.
Hope that helps!
Try Visual Code Studio! It’s free and Microsoft open-source! It works very well on OS X and Linux also.
Atom, Brackets, code pen, Visual Code Studio, Sublime, the options are endless!
Does my text-editor look appealing to you? You should know it’s Atom with the Seti UI and Seti Syntax Themes. You might like using it as a long term solution for writing code 
If you’re referring to it as a web pluggable to let users type code; then codemirror is the one that FCC uses.
I believe he’s asking whether or not there’s a “blank” version of the editor he can just type anything into (like as a scratchpad). That’s how I came to this page, at least, and the same thing I’m asking.
Right now I’m using PlayCode and Codepen, but would prefer just a blank FreeCodeCamp editor (with more options, if possible).
Is there a link to the editor without it being linked to a lesson?
Like the editor here, but blank:
https://www.freecodecamp.org/learn/javascript-algorithms-and-data-structures/intermediate-algorithm-scripting/sum-all-primes