Advanced Comments extension is merely an enhancement to standard VTiger comments functionality. It adds upto two picklist fields to the comments section and allows the user to “categorize” comments added. Also, these comments can be highlighted on the basis of configured picklist value, which makes it even more handy.
We have added yet another useful feature to this extension, named ‘View Previous Version’. It will enable user to view the changes made in it and stored in a log. With ‘ View Previous Version’ you can see the time when the changes are made along with the user who made them. To edit a comment, simply go to any module for which the comments are enabled. Click on the edit button under that comment, make the changes and save. You can see the original comment by clicking on the ‘View Previous version’ button under the comment.

In order to view the whole history of the modifications made in the comments, go to the ‘more’ button and select comments from the list of modules. There you’ll see a log in which all the modifications are saved. You can see the time modified and the user who made the changes.