After updating our Jira system from 7.9.2 to 7.12.1 we get a presentation error. All comments are showing up twice.
It seems that the second comment is without formatting and without newlines.
For better understanding here a screenshot

This happens to old comments (before the update) and new comments (after the update.
On the Icons above the comments, you see the trash can for deleting the comment. When I click on delete, both comments will be removed. So the comment is technically not duplicated rather than the comment is showing up twice.
Thanks a lot in advance for your help!