This is an extension of Brock Adams answer regarding the detection of userscripts by web administrators. Found here: link
What I'm going to discuss is hypothetical, as obviously avocation of this is not likely good behaviour.
Now. Userscripts in browser games. Let's take any browser game such as Neopets.
If you build a big fancy script to automate processes on any given neopets page, you likely need a control menu to activate various functions. One may use a floating iframe, or just add buttons on the page itself and hook them all up in the userscript.
The issue with this is that you're still changing the page itself, through addition or modification. Any administrator looking for scripts can check for triggered DOM manipulation events, could count iframe/input tags, etc.
My question is therefore, to minimize detection by administrators, how can you control different functions of a userscript running on a page without elements being added to the page itself (DOM)?