Leaving comments on a slide's Edit view can be a great way to mark your own ideas for later or to communicate with others when collaborating on a presentation.
You can leave comments on your own presentations or on any presentation where you have been invited to collaborate as a co-editor.
How to add a comment
In the Edit view, click on the Comments tab on the right side panel, then add your comment in the text field:
You'll find all comments for a given slide in the Comments tab, where you can edit or delete your own comments, reply to someone else's, or mark them as resolved.
Once comments have been marked as resolved, they will be collected and can be viewed again by clicking "Show X resolved comments":