Fix issuable sidebar icon of notification disabled

by adding the proper notification icon

app/helpers/notifications_helper.rb

@@ -106,9 +106,9 @@ module NotificationsHelper
     end
   end
-  def notification_setting_icon(notification_setting)
+  def notification_setting_icon(notification_setting = nil)
     sprite_icon(
-      notification_setting.disabled? ? "notifications-off" : "notifications",
+      !notification_setting.present? || notification_setting.disabled? ? "notifications-off" : "notifications",
       css_class: "icon notifications-icon js-notifications-icon"
     )
   end

app/views/shared/issuable/_sidebar.html.haml

@@ -139,7 +139,9 @@
       - if signed_in
         - if issuable_sidebar[:project_emails_disabled]
           .block.js-emails-disabled
-            = notification_description(:owner_disabled)
+            .sidebar-collapsed-icon.has-tooltip{ title: notification_description(:owner_disabled), data: { placement: "left", container: "body", boundary: 'viewport' } }
+              = notification_setting_icon
+            .hide-collapsed= notification_description(:owner_disabled)
         - else
           .js-sidebar-subscriptions-entry-point

changelogs/unreleased/fe-fix-issuable-sidebar-icon-of-notification-disabled.yml

+---
+title: Fix issuable sidebar icon on notification disabled
+merge_request: 32134
+author:
+type: fixed