rodocop, as i already wrote, user interface file(s) requires much more lines and much more time than file nsUserAgent.js. Macrolanguage is too poor language, but it is possible. JavaScript xul is a better option.
Once again, you are all invited and welcome to complete the user interface, don't be shy :)
For macrolanguage coders, it is easy to change the way, how to read preferences in file nsUse
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Extensions