Handle Ctrl+Enter while editing issue
While editing issue, Ctrl+Enter should invoke "Submit"
While creating new issue Ctrl+Enter should invoke "Create"
Many apps or services such as Gitlab, GitHub, Gmail, Outlook, Slack, Facebook, and Twitter support submitting a form by hitting Ctrl+Enter / ⌘+Return. I think that a lot of users are familiar with this shortcut key.
Redmine will be able to provide consistent UI with many other apps if the key combination is supported.