Fix 733

When files are uploaded, the cursor scrolls down to the last one and make it blink.
Just noticed that we also need to make sure we don't get infinite loops here in case the file is still not found.

I suggest to change `_nextPage` to return `true` when a page was appended and `false` when there are no more pages. This way you'll be able to jump out of this loop/function if the file name is never found for some reason.