Sharepoint Calendar view formatting

Hello, I am looking to add an icon to an item in a calendar view of a SharePoint list. In my list, a choice made in the category column adds to the content of the object column. It works quite well, I took inspiration from this page : https://alexanderhenkel.dk/post/010224-formatting-add-different-icons-to-a-choice-column/

I would like the same icon to display in calendar view mode. I made several attempts (JSON) without success.

Do you know if this is possible? Thank you for your response and for your help,
Stef