[Bug]: Accordion transitions are happening when the accordion is initially open

[kglickman]

Package

@carbon/react

Browser

Chrome

Package version

1.72.0

React version

18.3.1

Description

In this PR #17418, a fix was done to restore animation to the Accordions. The problem is that the transitions are happening when the accordion is initially open, not only when the user intentionally opens it. We have "pages" where we have accordions with a lot of content and they are open by default. The transition is jarring when this happens when the component first loads, particularly if the user is changing between one component with accordions to another.

Here is a video that demonstrates the issue

Screen.Recording.2025-01-31.095800.mp4

Reproduction/example

You can reproduce this in the storybook if you set the initial accordion to be open.

Steps to reproduce

See above about the storybook.

Suggested Severity

Severity 3 = User can complete task, and/or has a workaround within the user experience of a given component.

Application/PAL

No response

Code of Conduct

• I agree to follow this project's Code of Conduct
• I checked the current issues for duplicate problems