https://support.atlassian.com/jira-core-cloud/docs/what-is-a-jira-dashboard/
Not a Jira Dashboard
Ronin Dashboards (ref)
Dashboard vs wallboard
Datasources
Gadgets
Dashboards visibility
Use an existing Dashboard
Link to built-in dashboards description
Copy a dashboard
Create a new dashboard
Add gadgets
Arrange the layout
Slideshows
Share a dashboard
Set up a wallboard
Share for an existing or shared dashboard