How to reproduce :

• Go to Git service, in a git repository that has an open Pull Request
• Click on Pull Request tab,
• Then select the Pull request among the PR list.
• Click on the Changements tab
• Choose a file that has changed in the PR (prefer a file with a lot of changes : you will need to scroll down)
• At the first change, click on the line number to add a comment
• Write a comment but do not Submit (cf. image)
• Scroll down to the other changes in the file until you will no more see the previous comment area
• Scroll up

Result : The comment area is empty

Expected : The previously edited comment (but non validated) is displayed as it was left before the scroll

Sometimes a comment has been long to write and user need to see another part of the file before validating his comment. And it can be frustrating to loose the comment in this case. Wich lead to a lack of confidence in the Tuleap tool.

If it can help, we notice that this behavior happens for Diff unifié, and in the right column of Diff côte à côte. This behavior doesn't happen in the left column of Diff côte à côte.