There is a similar feature request about this but it’s from 2016 which predates the new Content Planner so I figured I would highlight this again.
In order to effectively switch from our current content platform to Slickplan (which I am dying to do), as an agency we need the ability for clients and internal team members to be able to add in-line comments within the Content Planner.
We currently do not plan to add inline commenting, however we have added the ability to comment on content blocks: How to add comments to your project?
This is also a necessary request tto move away from word docs for our copywriters writing content and getting it approved/proofed into SlickPlan. Please add this feature!