[Engineering] Several rather visible regression bugs on WMF sites (Special pages; PDF thumbnailing)

[Andre Klapper]

Please investigate if this is your area (and SWAT when appropriate):

Watchlist returns blank page or HTTP 503 error with "Hide: Page categorisation" /
MediaWiki\Linker\LinkRenderer::makeKnownLink() must implement interface MediaWiki\Linker\LinkTarget
https://phabricator.wikimedia.org/T164059 / 
https://phabricator.wikimedia.org/T143477 

Sight links in RecentChanges not longer available (when option "Hide reviewed edits" is not checked)
https://phabricator.wikimedia.org/T164049

PDF thumbnails fail to render on newly-uploaded PDF files
https://phabricator.wikimedia.org/T164045
(Chad also pointed to https://phabricator.wikimedia.org/T157644 in this context)

503 "Service Unavailable" error on Special:RevisionReview
https://phabricator.wikimedia.org/T164096
But intermittent and maybe just a one off, hence less urgent

The first three issues are pretty visible and I expect more discussions
on local village pumps. In addition to many local scripts/gadgets which
broke as a result of https://phabricator.wikimedia.org/T122755 (which
got announced in Tech News #16).

Thanks,
andre
-- 
Andre Klapper | Wikimedia Bugwrangler
http://blogs.gnome.org/aklapper/