The merge addon has a bug that when using the “align” connect, and when the text change has inserted lines on both editor. It can be easily reproduced by these steps:
- open codemirror home page: http://codemirror.net/index.html
- in the demo section, choose “merge/diff interface”.
- in “merge view demo”, edit the left side to add a few garbage lines which are not in the right side, these new lines are better spreaded to different places in the editor, for example, add 3 new garbage lines at line 10, 4 new garbage lines at line 30, 5 new garbage lines at line 50. Also delete a few lines on the left side so that the left side has new insertion lines.
- click to enable “align”. The issue happens also for not “align”, but more obvious for “align” mode.
- now, in left or right editor, roll the mousewheel up and down then let it go, you’ll see the funny scrolling behavior: it might jitter constantly without scrolling, or scroll up a distance then reset and scroll up again and again.