It will be amazing to have possibility add different credentials for different dashboard tabs.
Dear developers, maybe you can add credentials options in the dashboard tab settings.
With this option, we can add different rights to users (for example family members).
We have no current plans for this. Currently you would have to build this capability yourself. Maybe with the help of the ui-builder project that helps provide an interface from Node-RED to various UI frameworks.
This would be extremely hard. Given that the Dashboard is a single page app.
It is much easier to build multiple pages each with their own security. Some smart chap happens to have built something that might get you started - node-red-contrib-uibuilder. 
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