Great idea
I can’t get it to work, so maybe it’s me not the app. I drag the line to the text but it disappears

Enhance your iMessage conversations by adding colorful highlights to important messages. Easily peel, place, scale, and rotate stickers directly on message bubbles or photos for a more dynamic chat experience.
1.2
July 5, 2024
-Stability fixes along with new stickers.
Open iMessage, tap the App Store icon, then the four oval icon to access your app drawer. Select Message Highlighter Stickers! and tap to send stickers, or peel, hold, and drop them onto message bubbles or photos. You can scale and rotate them before placing.
Message Highlighter Stickers! is supported on iPhone, iPad, and iPod devices.
The app has an age rating of 4+, making it suitable for younger users and families.
Message Highlighter Stickers! is a paid app, available for $1.99.
The latest version, 1.2, was released on July 5, 2024.
No, Message Highlighter Stickers! does not contain advertisements.
The app has received one rating of 1.0 stars.
As the stickers are integrated into iMessage, an internet connection is typically required for sending messages, but the sticker functionality itself does not require a separate online service.