The New Issue View cannot fetch data when the Default Project Key Pattern is not respected

Issue Summary

The project key default pattern is the following:

[A-Z][A-Z0-9]+ 

If this pattern is not respected the following error will show up in the UI:

 We couldn't connect to that issue Make sure that this issue actually exists in that project. If it does, try again in a few minutes. If you still can't link to the issue, contact your Jira admin.  

And the following error is thrown on the dev tool:

:authority: monsoonconsulting.atlassian.net
:method: GET
:path: /rest/api/2/attachment/read/issue/SUP-857/credentials?maxTokenLength=65536


{data: {issue: null, project: null},…}
data: {issue: null, project: null}
issue: null
project: null
errors: [{path: ["project"], errorMessages: ["No project could be found with key 'SUP'."],…}]
0: {path: ["project"], errorMessages: ["No project could be found with key 'SUP'."],…}
errorMessages: ["No project could be found with key 'SUP'."]
message: "No project could be found with key 'SUP'."
path: ["project"]
0: "project"
statusCode: 404

Steps to Reproduce

1. Try to restore a backup from a Jira server instance in which the project key pattern is not respected.
2. Try to access the Jira issue in the new issue view

Expected Results

• See the content of the Jira issue.

Actual Results

Workaround

• Disable the new issue view in Personal Settings.
• Add the following to the URL:

   <instance_name>.atlassian.net/browse/<Issue_key>?oldIssueView=true 

• Rename the project key removing the unsupported character (this may cause some problems on customers side).

Notes:

The New Issue View enforcing mechanism has led clients to start facing this error in all projects. As the new issue view will be the default one next year, it will cause some impact on customers and also for the ones migrating to Cloud.