Making a custom auto resizing text box

[CADUS]

Hey everyone!

So I want to create something like this:

but animated, as an auto-resizing Textbox in After Effects. Creating an auto-resizing textbox from a rectangle is easy enough using expressions,  but I just can't figure out a way to create the "torn ends" or use my own shape instead of just a rectangle for this. Is there a way that I'm just not seeing or is this really just as complicated as I think it is?

[Mylenium]

There's nothing complicated about it. You are just not considering that the custom ends simply can exist as a separate layer. And that's basically the answer: You re-use the match that resizes the central box on the positions of the two ends, give or take a few modifications and then you are free to modify and style them as you want.

Mylenium

[CADUS]

So it took me a while to get to trying that, thank you for the suggestion! Bu to be honest, I've tried now for hours and I can't get it to work. Because it's been so long, I've described my new problem in a seperate forum post here: https://community.adobe.com/t5/after-effects/link-objects-to-autoscaling-boxes/m-p/11973733