I think you meant, you installed Stylebot and Stylebot gives the ability to click inside the box to change it's background color?
I never used Stylebot before, in fact, in all these years I avoided even using Greasemonkey. I broke down and gave in and installed Greasemonkey this morning to fix these new forum issues. This black style that jjflanigan made, he also had it for Greasemonkey and since I had already just installed that, I used his Greasemonkey version of the script. I tried clicking inside the code boxes etc with Greasemonkey active to see if I could change the elements like you said you were able to do with Stylebot but there's no choice that I could see to do this.