Update content in an editable datatable

I am trying to use editable datatable to allow user to add/update a justification for some work items in Dash. The justification usually is a paragraph. I found that if I want to edit the content of a cell, the original content will be overwritten. I can’t find a way to just insert some text without erase the original content. Is there something I missed or it is the default behavior? Is there any other component that can be used for that purpose? I know I can probably use textarea, but in this case it is a list of justifications and I want to add more justification to the list and may want to update certain justification.

Thanks

Xiali