Not all the links that are constructed by Special:Newpages don't pass through the CGI parameters that were used to load the page (including the offset, the namespace filter, and the page limit), and thus some links have the effect of canceling other ones.
To reproduce the bug:
- Go to Special:Newpages, click 'hide patrolled edits', then click '500'. The interface shows 500 pages with patrolled pages hidden.
- Reload Special:Newpages fresh, click '500' to see 500 pages, then click 'hide patrolled edits'. The interface returns to showing 50 pages, but with patrolled pages hidden.