App can't access issue data because of a lack of permission in Jira Cloud

Issue Summary

Migrated permission schemes, such as Default Permission Scheme are migrated and are not merged in cloud but renamed to  Default Permission Scheme (migrated) and all migrated projects use these migrated schemes.

The project role atlassian-addons-project-access is not added to any of these migrated permission schemes after being migrated.

Because of this apps cannot modify issues. As a result, issue operations fail with HTTP 400 or HTTP 403 status code with a message like Issue does not exist or you do not have permission to see it. or  You do not have permission to delete issues in this project.

This issue affects Jira Core, Jira Software and Jira Service Management.

Steps to Reproduce

1. In Jira Server create a project and use the Default Permission Scheme
2. Migrate the project with JCMA
3. In Admin → Issues → Permission schemes check if the migrated Default Permission Scheme (migrated) has atlassian-addons-project-access
4. Use an app that needs access to the project

Expected Results

Connect REST calls by the app are allowed and return expected data.

Actual Results

Operations fail with HTTP 400 or HTTP 403 status code with a message like Issue does not exist or you do not have permission to see it. or  {{You do not have permission to delete issues in this project.

Workaround

One

1. Migrate the users/groups and projects
2. Change the permission scheme for the project to the Default Permission Scheme in cloud that has atlassian-addons-project-access
3. Migrate again with users/groups, no projects and just apps

Two

Uninstall and re-install the marketplace app. This will apply the project role atlassian-addons-project-access to all existing projects. Access will now be available to the app.