Fixes #3943 - Title column is missing if ticket number is disabled in overview options.

app/assets/javascripts/app/controllers/ticket_overview.coffee

@@ -959,7 +959,7 @@ class Table extends App.Controller
       ticketListShow.push App.Ticket.find(ticket.id)
     @overview = App.Overview.find(overview.id)
     @table.update(
-      overviewAttributes: @overview.view.s
+      overviewAttributes: @convertOverviewAttributesToArray(@overview.view.s)
       objects:            ticketListShow
       groupBy:            @overview.group_by
       groupDirection:     @overview.group_direction
@@ -977,7 +977,6 @@ class Table extends App.Controller
     return if !overview && !tickets
 
     @view_mode = App.LocalStorage.get("mode:#{@view}", @Session.get('id')) || 's'
-    console.log 'notice', 'view:', @view, @view_mode
 
     App.WebSocket.send(event:'ticket_overview_select', data: { view: @view })
 
@@ -1177,7 +1176,7 @@ class Table extends App.Controller
 
       tableArguments =
         tableId:        "ticket_overview_#{@overview.id}"
-        overview:       @overview.view.s
+        overview:       @convertOverviewAttributesToArray(@overview.view.s)
         el:             @$('.table-overview')
         model:          App.Ticket
         objects:        ticketListShow
@@ -1249,6 +1248,15 @@ class Table extends App.Controller
           bulkAll.prop('indeterminate', true)
     )
 
+  convertOverviewAttributesToArray: (overviewAttributes) ->
+    # Ensure that the given attributes for the overview is an array,
+    #   otherwise some data might not be displayed.
+    # For more details, see https://github.com/zammad/zammad/issues/3943.
+    if !Array.isArray(overviewAttributes)
+      overviewAttributes = [overviewAttributes]
+
+    overviewAttributes
+
   renderCustomerNotTicketExistIfNeeded: (ticketListShow) =>
     user = App.User.current()
     @stopListening user, 'refresh'

spec/system/overview_spec.rb

@@ -324,4 +324,36 @@ RSpec.describe 'Overview', type: :system do
       end
     end
   end
+
+  context 'when only one attribute is visible', authenticated_as: :user do
+    let(:user) { create(:agent, groups: [group]) }
+    let(:group) { create(:group, name: 'aaa') }
+    let(:ticket) { create(:ticket, group: group, customer: user) }
+
+    let(:view) { { 's' => %w[title] } }
+    let(:condition) do
+      {
+        'ticket.customer_id' => {
+          operator: 'is',
+          value:    user.id
+        }
+      }
+    end
+    let(:overview) { create(:overview, condition: condition, view: view) }
+
+    let(:overview_table_head_selector) { 'div.table-overview table.table thead' }
+    let(:expected_header_text) { 'TITLE' }
+
+    before do
+      ticket
+
+      visit "ticket/view/#{overview.link}"
+    end
+
+    it 'shows only the title column' do
+      within :active_content, overview_table_head_selector do
+        expect(page).to have_css('th.js-tableHead[data-column-key="title"]', text: expected_header_text)
+      end
+    end
+  end
 end