View the original community article here
Last tested: Sep 13, 2018
If a LookML object is explicitly defined in both places, then the object from the extending dashboard/view/explore gets used.
For example, if we have suggestions: yes in a base view and in an extended view we specify suggestions: no, then the extended version "wins" out.
Note: link: does not extend in the way discussed above
Source: Docs
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