over the past 1,5 years WMDE’s Technical Wishes team was working on a major
improvement of wikidiff2  - the engine behind the wikitext diff view.
The major outcome of our improvements got deployed to most wikis just now:
It is now easier to find moved paragraphs and text changes inside them. 
Why we worked on this:
The idea for the project arose from the wishlist of the German-speaking
communities: Show text changes in moved paragraphs. Before we worked on
this, moved paragraphs were shown in the diff as a deleted paragraph and
then as an added paragraph. This meant that you had to parse visually
through the paragraphs to find any potential changes - a fact that vandals
liked to make use of. 
Desktop version, mobile version
The desktop version of the feature already got deployed to Mediawiki.org
and deWP in December 2017. After further improvements of the diff
algorithm, the change could now get deployed to most wikis. The languages
unified Han, Thai and Japanese that don’t use spaces as delimiters will
The mobile version is in the making and will follow in the next weeks. The
backend work has been done by the WMDE team, the WMF’s mobile team is
taking care of the design work for the user interface of the mobile version.
Improving the algorithm of wikidiff2: More than a new feature
The work that has been done goes further than the original wish: First of
all, we not only highlighted text changes within a moved paragraph, but
also made it easier to find moved paragraphs in the first place: Clickable
arrows allow to follow the move of the paragraph.
Second, we generally improved the diff algorithm: For example, we could
find an old bug in the diff engine: Sometimes two paragraphs which are not
related at all were considered a changed paragraph. The bug fix was already
deployed in October 2017. 
If you are interested in learning more about the work that has been done,
we're going to publish the lessons learned by the dev team within the next
days (so stay tuned :-) !.
We would like to thank everyone who supported us in the work around
wikidiff2: People from different wikis looked into diffs and gave us
valuable feedback. Moritz Mühlenhoff supported us by updating the library,
and deploying it. Tim Starling and Max Semenik supported us with code
review and consultation during the Vienna Hackathon. The Desktop and Mobile
Web team is going to add a user friendly design to the mobile version. Your
advice, feedback and support is much appreciated :-)
Further feedback is very welcome!
Birgit (for the technical wishes team)
 Extension manual: https://www.mediawiki.org/wiki/Extension:Wikidiff2
 Deployment ticket: https://phabricator.wikimedia.org/T195375
 Main project page on meta:
 Patch on gerrit for the bug fix:
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