If you're an editor, first, click on the element you want to add the comment to → click on the comment icon from the toolbar. Alternatively, use the keyboard shortcut Command + Option + M (Mac) or Ctrl + Option + M (PC).
If you're a viewer, click on the element you want to add the comment to → press the C key on your keyboard and the comment window will pop up.
You can drag / drop images or mention other members of the workspace by typing @ followed by their name.
Editing, Resolving, Deleting Comments
To edit a comment you've posted, click ... next to the comment you want to edit → Edit → Save the changes.
To delete a comment you've posted, click ... next to the comment you want to delete → Delete. Deleted comments cannot be restored.
To resolve a comment thread, click on the comment bubble → Resolve. Only editors can do this.
To hide all comments or just the resolved comments from the file, jump over to Comment Settings below.
Replying to Comments via Email
You can also add comments by replying to email notifications you've received. Email comments support rich text formatting and image upload:
Note: you can't mention a specific person from your workspace when replying to comments via email.
To change comment settings, click on the comment icon at the upper-right corner of the screen. Comment sidebar will pop up and you'll see Comment Settings at the bottom of the screen. You can change the following settings:
Show Comments on the Board
If you want to see all the commented elements on the board, check Show Comments on the Board. To hide all comments on the board, uncheck the box. You will still be able to see them in the Comment sidebar.
Show Resolved Comments
If you want all the resolved comments to be visible on the board as well as the comment sidebar, check Show Resolved Comments or uncheck it if you want to hide resolved comments. When shown, resolved comments will appear greyed out in the comment sidebar.
Receive Notifications for All Comments
To subscribe to / unsubscribe from comment notifications via email, open the file that you want to unsubscribe from, click on the comment icon → Comment Settings → check / uncheck Receive Notifications for All Comments:
Note: Unsubscribe / subscribe is associated with the specific file you're in.