Vars to determine if we have overwrite OK permission from user or
there's no conflict with filenames, so it's a new one and we can save
Don't check for DOM node to decide if we can save or not anymore,
instead run an XHR that ends up setting lastFileDirCheckStatusObj from
false to something
On spotting that, clear the interval and continue by asking user if they
want to overwrite, or if there's no conflict, set that value instead
If we have no newFileName or we have one but no permission to overwrite
yet, set the content for use in a moment under saveAsContent and we loop
back around
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