Originally Posted by Byron Kinnaman
JUst pile more on top and you are still worried pile a bit more.
Sarcasm… I hope! LOL…
Personally, I wouldn't do anything unless (1) it is leaking, and/or (2) you are ready to do a proper reseal of the window. That involves removing the window, cleaning down to bare fiberglass, and reinstalling with fresh butyl tape. A properly installed window should not need any caulk. The butyl does it all. A search on YouTube for "reseal RV window" should turn up a helpful tutorial.
When you're ready to do it properly, a Google site search on "remove silicone" will bring up many old threads on how to get rid of the old stuff. It's mostly mechanical, with chemical clean-up at the end. If you haven't found it yet, the Google site search is a great tool. Look at the blue bar at the top under your log-in information, "Search," and all the way down to "Site search/Google".
Here's one thread to get you started
. It has some good information and links. Just ignore the part about using gasoline!