Pre-populated comments does not work in transition screen

Summary

When adding comments in transition screen, the pre-populated comments does not work

Workaround

The pre-populated comment functionality still works at the comment section in View issue screen.

Environment

Replicated in these versions:

• JIRA v7.2.0-OD-03-010
• JIRA Service Desk v3.2.0-OD-04-003

Steps to Reproduce

1. Create a Service Desk project
2. Create a request in this project
3. Make sure you have a transition to the customer with comments (should be there by default as 'Respond to Customer')
4. Click the transition

Expected Results

Pre-populated comments are populated in the comments.

Actual Results

The pre-populated comments are not populated in the comments.

No errors in logs

There was a similar bug:
https://jira.atlassian.com/browse/JSD-3473