UX: Enable new notifications menu by default (#21060)

https://meta.discourse.org/t/260358

config/locales/server.en.yml

@@ -2406,7 +2406,7 @@ en:
     navigation_menu: "Determine which navigation menu to use. Sidebar and header navigation are customizable by users. Legacy option is available for backward compatibility."
     default_sidebar_categories: "Selected categories will be displayed under Sidebar's Categories section by default."
     default_sidebar_tags: "Selected tags will be displayed under Sidebar's Tags section by default."
-    enable_new_notifications_menu: "Enables the new notifications menu for the legacy navigation menu."
+    enable_new_notifications_menu: "Enables the new notifications menu. Disabling this setting is deprecated. The new notifications menu is always used for non-legacy 'navigation menu' choices. <a href='https://meta.discourse.org/t/260358'>Learn more</a>"
     enable_experimental_hashtag_autocomplete: "EXPERIMENTAL: Use the new #hashtag autocompletion system for categories and tags that renders the selected item differently and has improved search"
     experimental_new_new_view_groups: "EXPERIMENTAL: Enable a new topics list that combines unread and new topics and make the \"Everything\" link in the sidebar link to it."
     enable_custom_sidebar_sections: "EXPERIMENTAL: Enable custom sidebar sections"
@@ -2467,7 +2467,6 @@ en:
       discourse_connect_cannot_be_enabled_if_second_factor_enforced: "You cannot enable DiscourseConnect if 2FA is enforced."
       delete_rejected_email_after_days: "This setting cannot be set lower than the delete_email_logs_after_days setting or greater than %{max}"
       invalid_uncategorized_category_setting: 'The "Uncategorized" category cannot be selected if ''allow uncategorized topics'' is not enabled.'
-      enable_new_notifications_menu_not_legacy_navigation_menu: "You must set `navigation_menu` to `legacy` before enabling this setting."
       invalid_search_ranking_weights: "Value is invalid for search_ranking_weights site setting. Example: '{0.1,0.2,0.3,1.0}'. Note that maximum value for each weight is 1.0."
 
     placeholder:

config/site_settings.yml

@@ -2116,8 +2116,7 @@ navigation:
       - "default"
       - "unread_new"
   enable_new_notifications_menu:
-    default: false
+    default: true
-    validator: "EnableNewNotificationsMenuValidator"
   enable_custom_sidebar_sections:
     client: true
     type: group_list

lib/validators/enable_new_notifications_menu_validator.rb

@@ -1,15 +0,0 @@
-# frozen_string_literal: true
-
-class EnableNewNotificationsMenuValidator
-  def initialize(opts = {})
-  end
-
-  def valid_value?(value)
-    return true if value == "f"
-    SiteSetting.navigation_menu == "legacy"
-  end
-
-  def error_message
-    I18n.t("site_settings.errors.enable_new_notifications_menu_not_legacy_navigation_menu")
-  end
-end

spec/lib/validators/enable_new_notifications_menu_validator_spec.rb

@@ -1,18 +0,0 @@
-# frozen_string_literal: true
-
-RSpec.describe EnableNewNotificationsMenuValidator do
-  it "does not allow `enable_new_notifications_menu` site settings to be enabled when `navigation_menu` site settings is not set to `legacy`" do
-    SiteSetting.navigation_menu = "sidebar"
-
-    expect { SiteSetting.enable_new_notifications_menu = true }.to raise_error(
-      Discourse::InvalidParameters,
-      /#{I18n.t("site_settings.errors.enable_new_notifications_menu_not_legacy_navigation_menu")}/,
-    )
-  end
-
-  it "allows `enable_new_notifications_menu` site settings to be enabled when `navigation_menu` site settings is set to `legacy`" do
-    SiteSetting.navigation_menu = "legacy"
-
-    expect { SiteSetting.enable_new_notifications_menu = true }.to_not raise_error
-  end
-end

spec/serializers/current_user_serializer_spec.rb

@@ -283,8 +283,9 @@ RSpec.describe CurrentUserSerializer do
       )
     end
 
-    it "isn't included when navigation menu is legacy" do
+    it "isn't included when navigation menu is legacy with old user menu" do
       SiteSetting.navigation_menu = "legacy"
+      SiteSetting.enable_new_notifications_menu = false
 
       expect(serializer.as_json[:new_personal_messages_notifications_count]).to be_nil
     end