The beta feature Two column edit conflict from WMDE’s Technical Wishes team was released in early 2017 to make the handling of edit conflicts more intuitive. Now, the team will replace their beta feature with a new version, which allows to merge conflicting revisions line by line. If you want to give it a try, activate the feature in your preferences. The feature will automatically be replaced for people who use the current beta feature. As always, feedback is very welcome!
Thanks!