Fixes #3378 - Spaces stay URL-encoded when going back to search results on KB for agents.

app/assets/javascripts/app/controllers/knowledge_base/search_controller.coffee

@@ -14,7 +14,8 @@ class App.KnowledgeBaseSearchController extends App.Controller
       return_path: @parentController.getKnowledgeBase().uiUrl(@parentController.kb_locale(), 'search')
     )
 
-    if query = @parentController.lastParams.arguments
+    if @parentController.lastParams.arguments
+      query = decodeURIComponent(@parentController.lastParams.arguments)
       @searchFieldPanel.widget.startSearch(query)
 
     @searchFieldPanel.widget.focus()

spec/system/knowledge_base/locale/search_spec.rb

@@ -0,0 +1,37 @@
+# Copyright (C) 2012-2021 Zammad Foundation, http://zammad-foundation.org/
+
+require 'rails_helper'
+
+RSpec.describe 'Knowledge Base Locale Search', type: :system do
+  include_context 'basic Knowledge Base'
+
+  let!(:answer_for_search) { create(:knowledge_base_answer, category: category, translation_attributes: { title: 'A example title' }) }
+
+  context 'when search query is directly used inside the url' do
+    let(:search_query) { nil }
+
+    before do
+      visit "#knowledge_base/#{knowledge_base.id}/locale/#{locale_name}/search/#{search_query}"
+    end
+
+    shared_examples 'check search result' do
+      it 'answer exists in search result' do
+        within :active_content do
+          expect(page).to have_css('.knowledge-base-main .section', text: answer_for_search.translations.first.title)
+        end
+      end
+    end
+
+    context 'when search query is a single word' do
+      let(:search_query) { 'Example' }
+
+      include_examples 'check search result'
+    end
+
+    context 'when search query has encoded characters' do
+      let(:search_query) { 'A%20Example' }
+
+      include_examples 'check search result'
+    end
+  end
+end