Alle Kategorien stummschalten, aber

So you want to mute all categories in the settings of the group except for the ones that are watched or where the first post is watched?

I think you could use data explorer to provide you a list of the category IDs separated with | so you can paste it directly into the group setting.

Like this:

Is that what you had in mind?

This is the query I used to get that list:

--[params]
-- group_id :group

WITH excluded_categories AS (
  SELECT category_id
  FROM group_category_notification_defaults
  WHERE group_id = :group
    AND notification_level IN (3, 4)
),
category_names AS (
  SELECT id
  FROM categories
  WHERE id NOT IN (SELECT category_id FROM excluded_categories)
)
SELECT string_agg(CAST(id AS TEXT), '|') AS category_list
FROM category_names;
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