Hi Andrew,
I didnt get your point Andrew. We need to rewrite the code in custom.js again right when we deploy the Workflow in 2.3 as new folder will be created "Generated Hybrid App".
And in the console I got the below warning message
"Warning: Switching from Generated Workflow to Generated Hybrid App, custom code changes/additions will need to be moved over manually"
Thanks & Regards,
Goutham.