Please add some functionality to auto-size cell comment on comment length. Because comments size depends on column and row size, sometimes comments are not readable. Especial if Clientanchor is not given position and size, it's set to row 0 and column 0 with the size of it.
I'm having a difficult time understanding what you want POI to do here. Could you include some code to demonstrate the problem you're experiencing? As you pointed out, Comment [1] and ClientAnchor [2] don't have an autosize method. What are you doing right now to determine the ideal size of your Comment? [1] https://poi.apache.org/apidocs/org/apache/poi/ss/usermodel/Comment.html#getClientAnchor%28%29 [2] https://poi.apache.org/apidocs/org/apache/poi/ss/usermodel/ClientAnchor.html