In confluence cloud, it appears that a person can enter Jira issue keys as text while in page edit mode:

However, when the page is in display mode, the issue keys are converted to jira links:

It appears there is some automated functionality to convert the text to urls.
This same behavior is not working in Jira Data Center.
Is this auto-conversion a function of Cloud? If so, is it done via an add-on, or a some basic configuration setting, or some other functionality?
Can this same functionality be put in place in Confluence Data Center? If so, how?