I just base on info and assume that group should be visible by default.
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Groups allow the user to combine multiple entities into one. A group can be promoted to a view by setting view: true under the group definition. This will make the group available as a new tab in the frontend.
By default, every group appears in the HOME tab. If you create a group default_view it will REPLACE the contents of the HOME tab so you can customize the HOME tab as you wish.
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is only applicable to non-Lovelace interface.
When using Lovelace, groups do not influence on the frontend and are used only for grouping entities logically…
Could you post the url of your HA page?