JIRA.Issue.getIssueId() doesn't work for Next-Gen based projects and NewIssue view with classic-Jira project

Summary

JIRA.Issue.getIssueId() doesn't work for Next-Gen based projects and NewIssue view with classic project

Steps to Reproduce

1. Browse to any NextGen project issue or any ClassicProject Issue with New-view only
2. Open Devtool >> Console
3. write below javascript and press enter

   JIRA.Issue.getIssueId()  

1. JIRA.Issue.getIssueId() - returns null

Expected Results

JIRA.Issue.getIssueId() should return 'IssueId' as in below screenshot

JIRA.Issue.getIssueKey() should return 'IssueKey'

Note: Above is working in ClassicProject with Old-Issue-View only.

Actual Results

 Both JIRA.Issue.getIssueId() & JIRA.Issue.getIssueKey() - return null as in below screenshots