Deleting A String From Firefox's about:config

I got frustrated the other day searching for a way to delete a string from the firefox about:config page. I messed it up trying to do some firefox speed up trick; lesson learned never mess with my sweet firefox. So after looking around and not being able to find a proper guide I had to deal with it myself which took an hour or two. So just to save my users a big headache like I got here's a nice little guide to deleting a string in Firefox's about:config. Basically I found out you can't just do it from firefox itself you have to go into the actual user file:

1. Close firefox (so not to mess it up even more).
2. Go into your profile page "%AppData%\Mozilla\Firefox\Profiles\xxxxxxxx.default\" the x's stand for a randomly generated code for every profile.
3. Open the file "prefs.js" in a text editor.
4. And just use the find tool and enter the title of the string. (not the whole title just a part if you want) and just erase that part.

Well there you go no more headaches when the time comes for you guys.

Thank You