I don't have any car stickers apart from the manufacturer's, so I had no idea you could end up in court for a car sticker!
You learn something new every day. It feels like a bit of a waste of court time and costs, maybe an advisory would have been sufficient.
https://www.theguardian.com/uk-news/2025/jan/29/chester-woman-stand-trial-accused-displaying-threatening-bumper-sticker