Oct 17 2019
I don't think this is needed anymore, the filter is disabled and we don't have a massive problem with vandalism.
You are right, @DannyS712 . I think these one on the other hand are: https://pt.wikipedia.org/w/index.php?target=Tuga1143&namespace=all&tagfilter=&start=&end=2019-05-31&limit=50&title=Especial%3AContribui%C3%A7%C3%B5es
Oct 15 2019
Aug 21 2018
Mar 14 2018
Jul 13 2017
Sep 6 2016
It seems that pages protected before march 2014 don't show that data: https://en.wikipedia.org/w/index.php?title=Special:ProtectedPages&offset=459647&namespace=12&type=edit&level=0&sizetype=min&size=; https://pt.wikipedia.org/w/index.php?title=Especial:P%C3%A1ginas_protegidas&offset=56259&namespace=0&type=edit&level=0&sizetype=min&size=
As far as i remember (I hadn't looked through that page in years, probably 2010), this didn't happen before.
Jul 8 2016
We announced the beta test on the Watchlist from June to October 2013 https://pt.wikipedia.org/w/index.php?title=MediaWiki%3AWatchlist-details&type=revision&diff=37047797&oldid=36119894, but I don't know if that has anything to do with the popularity of the feature among registered users. We did not see much resistance to its use as on many other languages, but again I can not explain why. Portuguese Wikipedia is also not as techy-driven as other language versions. There is only a handful of editors with programming skills. I personally started using it mostly because of citoid and my aversion of filling out citation templates by hand.
Jun 9 2016
I just had the same problem on ptwiki. I received notification but no email. Asked somebody else to send a test email, and received both the notification and the email, so we figure that the problem might be in the bounced message having an email address within it and it bounced because of that.