Add customer tag by user action in storefront.
When customer submit the form, “User Tag Plus” app can add certain customer tag to the customer.
So when customer clicks “enroll to the event” button, you can add “EVENT2025” tag to the customer.
Then using our Howdy Customer Profile app, you can show event banner for “EVENT2025” tagged customers.
User Tag Plus|ボタンワンクリックで顧客タグ付与 - オンラインショップ上でボタンを押すことで任意のタグ付けが可能 | Shopify App Store
https://apps.shopify.com/user-tag-plus-1