Fixes #3748: Ticket in the ticket creation screen tags are shown after 2 characters, in the ticket zoom after 1 character.

app/assets/javascripts/app/controllers/_ui_element/tag.coffee

@@ -11,7 +11,7 @@ class App.UiElement.tag
         createTokensOnBlur: true
         autocomplete: {
           source: source
-          minLength: 2
+          minLength: 1
           response: (e, ui) ->
             return if !ui
             return if !ui.content

app/assets/javascripts/app/controllers/widget/tag.coffee

@@ -57,7 +57,7 @@ class App.WidgetTag extends App.Controller
     source = "#{App.Config.get('api_path')}/tag_search"
     @$('.js-newTagInput').autocomplete(
       source: source
-      minLength: 0
+      minLength: 1
       response: (e, ui) =>
         return if !ui
         return if !ui.content

spec/system/knowledge_base/locale/answer/edit_spec.rb

@@ -108,6 +108,16 @@ RSpec.describe 'Knowledge Base Locale Answer Edit', type: :system do
       end
     end
 
+    it 'triggers autocomplete after one character' do
+      within :active_content do
+        click '.js-newTagLabel'
+
+        elem = find('.js-newTagInput')
+        elem.fill_in with: 'e'
+        expect(page).to have_css('ul.ui-autocomplete > li.ui-menu-item', minimum: 1)
+      end
+    end
+
     it 'shows an existing tag' do
       within :active_content do
         expect(page).to have_css('a.js-tag', text: published_answer_tag_name)