i say just leave it. it will be really difficult to find the exact shade of white to fix it (unless you want to repaint the entire window section). Given the size of the window, you will need to be very precise.
My Trackmaster/Tomy/Plarail Photo Gallery Page (over 600+ photos and still under construction)
https://www.flickr.com/photos/183311600@N03/
https://www.flickr.com/photos/183311600@N03/
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