Redmine

If the access settings for the role specify the right to edit comments on the task, the user can also delete them.
It would be great if it were possible to differentiate the functions of editing and deleting comments by making them separate permissions. For example, a user could edit comments, but not delete them.

However, all these features will be useless if the history of changes to comments is not saved. Therefore, I suggest adding these two functions to the new versions of the system.