Today at work I was using impatient-mode to share some code with Brian. It makes for a really handy live pastebin. To limit the buffer to the relevant code, I narrowed it down with narrow-to-region. However, the browser wouldn’t update to show only the narrowed region until I made an edit. This makes sense because impatient-mode hooks after-change-functions. Narrowing the buffer doesn’t change anything in the buffer, so, as expected, this hook is not called.