Three comments exist: Reader, reviewer, and change comments.
This function will only be available if the document has had a prior revision to track changes from.
If you click on the delta next to your change --> Add change log comment --> write the content, you can mark it as Minor or important if needed, allowing you to filter comments in the change log module.
Looking at the navigation bar at the bottom, there is a change comment icon made to navigate you through comments that have been added to revision deltas in a document. This tool allows you to skip through the document to see the comments added to a specific section.
If you click on Author --> Change log comments --> it shows all the change comments made for the next revision. When clicking on a comment, you are taken to the page where the comment was made. The number next to the Change log indicates the amount of comments. Comments can be deleted by clicking on the Trash icon:
Comments can be filtered by all revisions or a specific revision by selecting the desired option from the filter menu above the comments list.