diff --git a/app/assets/stylesheets/application.scss b/app/assets/stylesheets/application.scss
index 083317b65..312833c6c 100644
--- a/app/assets/stylesheets/application.scss
+++ b/app/assets/stylesheets/application.scss
@@ -1111,3 +1111,7 @@ td.day .calendar-text {
   display: flex;
   justify-content: center;
 }
+
+.tag-topic, .tag-operation {
+  text-decoration: none;
+}
diff --git a/app/helpers/materials_helper.rb b/app/helpers/materials_helper.rb
index 9ccd964d3..b1d245014 100644
--- a/app/helpers/materials_helper.rb
+++ b/app/helpers/materials_helper.rb
@@ -71,17 +71,15 @@ def display_attribute(resource, attribute, show_label: true, title: nil, markdow
     ].any?
 
     value = resource.send(attribute)
-    if markdown
-      value = render_markdown(value)
-    end
+    value = render_markdown(value) if markdown
     if value.present?
-      if list
-        value = value.map do |v|
-          html_escape(block_given? ? yield(v) : v)
-        end
-      else
-        value = html_escape(block_given? ? yield(value) : value)
-      end
+      value = if list
+                value.map do |v|
+                  html_escape(block_given? ? yield(v) : v)
+                end
+              else
+                html_escape(block_given? ? yield(value) : value)
+              end
     end
     string = "<p class=\"#{attribute}#{show_label ? ' no-spacing' : ''}\">"
     unless value.blank? || value.try(:strip) == 'License Not Specified'
@@ -119,18 +117,31 @@ def embed_youtube(material)
   def keywords_and_topics(resource, limit: nil)
     tags = []
 
-    %i[scientific_topic_names operation_names keywords].each do |field|
-      tags |= resource.send(field) if resource.respond_to?(field)
+    if resource.respond_to?(:scientific_topics)
+      tags += resource.scientific_topics.map do |term|
+        content_tag(:span, class: 'label label-info tag-topic') do
+          content_tag(:i, '', class: 'fa fa-flask') + ' ' + term.preferred_label
+        end
+      end
     end
 
-    limit_exceeded = limit && (tags.length > limit)
-    tags = tags.first(limit) if limit
+    if resource.respond_to?(:operations)
+      tags += resource.operations.map do |term|
+        content_tag(:span, class: 'label label-info tag-operation') do
+          content_tag(:i, '', class: 'fa fa-cogs') + ' ' + term.preferred_label
+        end
+      end
+    end
 
-    elements = tags.map do |tag|
-      content_tag(:span, tag, class: 'label label-info')
+    if resource.respond_to?(:keywords)
+      tags += resource.keywords.map do |tag|
+        content_tag(:span, tag, class: 'label label-info tag-keyword')
+      end
     end
-    elements << '&hellip;' if limit_exceeded
 
-    elements.join(' ').html_safe
+    limit_exceeded = limit && (tags.length > limit)
+    tags = tags.first(limit) if limit
+    tags << '&hellip;'.html_safe if limit_exceeded
+    safe_join(tags, ' ')
   end
 end
diff --git a/app/views/common/_extra_metadata.html.erb b/app/views/common/_extra_metadata.html.erb
index d32155ece..92ed02ddf 100644
--- a/app/views/common/_extra_metadata.html.erb
+++ b/app/views/common/_extra_metadata.html.erb
@@ -63,7 +63,9 @@
 <%= display_attribute(resource, :contributors) { |values| values.join(', ') } if resource.respond_to?(:contributors) %>
 <%= display_attribute(resource, :remote_created_date) if resource.respond_to?(:remote_created_date) %>
 <%= display_attribute(resource, :remote_updated_date) if resource.respond_to?(:remote_updated_date) %>
-<%= display_attribute(resource, :scientific_topics) { |values| values.map { |x| x.preferred_label }.join(', ') } %>
+<%= display_attribute(resource, :scientific_topics) { 
+  |values| safe_join(values.map { |x| link_to(x.preferred_label, x.uri, target: '_blank') }, ', ') 
+} %>
 
 <% if resource.is_a?(LearningPath) %>
   <%= display_attribute(resource, :status) { |value| material_status_title_for_label(value) } %>
@@ -73,5 +75,7 @@
 <% end %>
 
 <% if resource.respond_to?(:operations) -%>
-  <%= display_attribute(resource, :operations) { |values| values.map { |x| x.preferred_label }.join(', ') } %>
+  <%= display_attribute(resource, :operations) { 
+    |values| safe_join(values.map { |x| link_to(x.preferred_label, x.uri, target: '_blank') }, ', ') 
+  } %>
 <% end %>
diff --git a/test/controllers/learning_paths_controller_test.rb b/test/controllers/learning_paths_controller_test.rb
index fa2f34358..1cf40a752 100644
--- a/test/controllers/learning_paths_controller_test.rb
+++ b/test/controllers/learning_paths_controller_test.rb
@@ -12,7 +12,7 @@ class LearningPathsControllerTest < ActionController::TestCase
       description: 'New description'
     }
   end
-  #INDEX TESTS
+  # INDEX TESTS
   test 'should get index' do
     get :index
     assert_response :success
@@ -49,7 +49,7 @@ class LearningPathsControllerTest < ActionController::TestCase
     assert_equal learning_paths_path, body['links']['self']
   end
 
-  #NEW TESTS
+  # NEW TESTS
 
   test 'should get new page for curators and admins only' do
     get :new
@@ -72,14 +72,14 @@ class LearningPathsControllerTest < ActionController::TestCase
     assert_response :success
   end
 
-  #EDIT TESTS
+  # EDIT TESTS
   test 'should not get edit page for not logged in users' do
-    #Not logged in = Redirect to login
+    # Not logged in = Redirect to login
     get :edit, params: { id: @learning_path }
     assert_redirected_to new_user_session_path
   end
 
-  #logged in but insufficient permissions = ERROR
+  # logged in but insufficient permissions = ERROR
   test 'should get edit for learning_path owner' do
     sign_in @learning_path.user
     get :edit, params: { id: @learning_path }
@@ -93,20 +93,20 @@ class LearningPathsControllerTest < ActionController::TestCase
   end
 
   test 'should get edit for admin' do
-    #Owner of learning_path logged in = SUCCESS
+    # Owner of learning_path logged in = SUCCESS
     sign_in users(:admin)
     get :edit, params: { id: @learning_path }
     assert_response :success
   end
 
   test 'should not get edit page for regular user' do
-    #Administrator = SUCCESS
+    # Administrator = SUCCESS
     sign_in users(:another_regular_user)
     get :edit, params: { id: @learning_path }
     assert :forbidden
   end
 
-  #CREATE TEST
+  # CREATE TEST
   test 'should create learning_path for curator' do
     sign_in users(:curator)
     assert_difference('LearningPath.count') do
@@ -146,7 +146,7 @@ class LearningPathsControllerTest < ActionController::TestCase
     assert_redirected_to new_user_session_path
   end
 
-  #SHOW TEST
+  # SHOW TEST
   test 'should show learning_path' do
     get :show, params: { id: @learning_path }
     assert_response :success
@@ -183,21 +183,22 @@ class LearningPathsControllerTest < ActionController::TestCase
     assert_equal learning_path_path(assigns(:learning_path)), body['data']['links']['self']
   end
 
-  #UPDATE TEST
+  # UPDATE TEST
   test 'should update learning_path' do
     sign_in @learning_path.user
     patch :update, params: { id: @learning_path, learning_path: @updated_learning_path }
     assert_redirected_to learning_path_path(assigns(:learning_path))
   end
 
-  test "should add topics to learning_path" do
+  test 'should add topics to learning_path' do
     sign_in @learning_path.user
     learning_path = learning_paths(:two)
     assert_no_difference('LearningPathTopic.count') do
       assert_difference('LearningPathTopicLink.count', 1) do
         assert_difference('learning_path.topics.count', 1) do
           patch :update, params: { learning_path: {
-            topic_links_attributes: { '1': { topic_id: learning_path_topics(:goblet_things).id, order: 300 } } },
+                                     topic_links_attributes: { '1': { topic_id: learning_path_topics(:goblet_things).id, order: 300 } }
+                                   },
                                    id: learning_path.id }
         end
       end
@@ -211,14 +212,15 @@ class LearningPathsControllerTest < ActionController::TestCase
     assert_equal learning_path_topics(:goblet_things), links[1].topic
   end
 
-  test "should remove topic from learning_path" do
+  test 'should remove topic from learning_path' do
     sign_in @learning_path.user
     learning_path = learning_paths(:two)
     assert_no_difference('LearningPathTopic.count') do
       assert_difference('LearningPathTopicLink.count', -1) do
         assert_difference('learning_path.topics.count', -1) do
           patch :update, params: { learning_path: {
-            topic_links_attributes: { '1': { id: learning_path.topic_link_ids.first, _destroy: '1' } } },
+                                     topic_links_attributes: { '1': { id: learning_path.topic_link_ids.first, _destroy: '1' } }
+                                   },
                                    id: learning_path.id }
         end
       end
@@ -227,7 +229,7 @@ class LearningPathsControllerTest < ActionController::TestCase
     assert_empty assigns(:learning_path).topic_links
   end
 
-  test "should modify items in learning_path" do
+  test 'should modify items in learning_path' do
     sign_in @learning_path.user
 
     l1 = @learning_path.topic_links[0]
@@ -248,7 +250,7 @@ class LearningPathsControllerTest < ActionController::TestCase
     end
   end
 
-  #DESTROY TEST
+  # DESTROY TEST
   test 'should destroy learning_path owned by user' do
     sign_in @learning_path.user
     assert_difference('LearningPath.count', -1) do
@@ -273,9 +275,8 @@ class LearningPathsControllerTest < ActionController::TestCase
     assert_response :forbidden
   end
 
-
-  #CONTENT TESTS
-  #BREADCRUMBS
+  # CONTENT TESTS
+  # BREADCRUMBS
   test 'breadcrumbs for learning_paths index' do
     get :index
     assert_response :success
@@ -326,7 +327,7 @@ class LearningPathsControllerTest < ActionController::TestCase
     end
   end
 
-  #OTHER CONTENT
+  # OTHER CONTENT
   test 'learning path lists topics' do
     sign_in(users(:regular_user))
 
@@ -344,8 +345,8 @@ class LearningPathsControllerTest < ActionController::TestCase
     get :show, params: { id: @learning_path }
 
     assert_response :success
-    assert_select 'a.btn[href=?]', edit_learning_path_path(@learning_path), count: 0 #No Edit
-    assert_select 'a.btn[href=?]', learning_path_path(@learning_path), count: 0 #No Edit
+    assert_select 'a.btn[href=?]', edit_learning_path_path(@learning_path), count: 0 # No Edit
+    assert_select 'a.btn[href=?]', learning_path_path(@learning_path), count: 0 # No Edit
   end
 
   test 'do not show action buttons when not owner or admin' do
@@ -353,8 +354,8 @@ class LearningPathsControllerTest < ActionController::TestCase
 
     get :show, params: { id: @learning_path }
 
-    assert_select 'a.btn[href=?]', edit_learning_path_path(@learning_path), count: 0 #No Edit
-    assert_select 'a.btn[href=?]', learning_path_path(@learning_path), count: 0 #No Edit
+    assert_select 'a.btn[href=?]', edit_learning_path_path(@learning_path), count: 0 # No Edit
+    assert_select 'a.btn[href=?]', learning_path_path(@learning_path), count: 0 # No Edit
   end
 
   test 'show action buttons when learning_path_curator' do
@@ -375,7 +376,7 @@ class LearningPathsControllerTest < ActionController::TestCase
     assert_select 'a.btn[href=?]', learning_path_path(@learning_path), text: 'Delete', count: 1
   end
 
-  #API Actions
+  # API Actions
   test 'should not allow access to private learning_paths' do
     sign_in users(:regular_user)
     get :show, params: { id: learning_paths(:in_development_learning_path) }
@@ -453,11 +454,11 @@ class LearningPathsControllerTest < ActionController::TestCase
 
     assert_difference('LearningPathTopicLink.count', -1) do
       patch :update, params: { learning_path: {
-        topic_links_attributes: { '1': { id: @learning_path.topic_link_ids.first, _destroy: '1' } } },
+                                 topic_links_attributes: { '1': { id: @learning_path.topic_link_ids.first, _destroy: '1' } }
+                               },
                                id: @learning_path.id }
       assert_redirected_to learning_path_path(assigns(:learning_path))
     end
-
   end
 
   test 'should not allow non-collaborator to edit' do
@@ -511,10 +512,10 @@ class LearningPathsControllerTest < ActionController::TestCase
     end
 
     response_materials = body.dig('data', 'relationships', 'materials', 'data')
-    assert_equal [materials[1].id, materials[0].id, materials[2].id], response_materials.map { |m| m['id'].to_i }
+    assert_equal([materials[1].id, materials[0].id, materials[2].id], response_materials.map { |m| m['id'].to_i })
 
     response_events = body.dig('data', 'relationships', 'events', 'data')
-    assert_equal [events[1].id, events[0].id], response_events.map { |e| e['id'].to_i }
+    assert_equal([events[1].id, events[0].id], response_events.map { |e| e['id'].to_i })
   end
 
   test 'should include back-reference to learning path in item links' do
diff --git a/test/controllers/materials_controller_test.rb b/test/controllers/materials_controller_test.rb
index e41945e12..bf37993a5 100644
--- a/test/controllers/materials_controller_test.rb
+++ b/test/controllers/materials_controller_test.rb
@@ -24,10 +24,10 @@ class MaterialsControllerTest < ActionController::TestCase
     @monitor = @failing_material.create_link_monitor(url: @failing_material.url, code: 404, fail_count: 5)
   end
 
-  #Tests
+  # Tests
   # INDEX, NEW, EDIT, CREATE, SHOW, BREADCRUMBS, TABS, API CHECKS
 
-  #INDEX TESTS
+  # INDEX TESTS
   test 'should get index' do
     get :index
     assert_response :success
@@ -121,7 +121,7 @@ class MaterialsControllerTest < ActionController::TestCase
     assert_select '.broken-link-notice', text: /this material's URL.+since 2 April 2023/
   end
 
-  #NEW TESTS
+  # NEW TESTS
   test 'should get new' do
     sign_in users(:regular_user)
     get :new
@@ -129,11 +129,11 @@ class MaterialsControllerTest < ActionController::TestCase
   end
 
   test 'should get new page for logged in users only' do
-    #Redirect to login if not logged in
+    # Redirect to login if not logged in
     get :new
     assert_response :redirect
     sign_in users(:regular_user)
-    #Success for everyone else
+    # Success for everyone else
     get :new
     assert_response :success
     sign_in users(:admin)
@@ -147,14 +147,14 @@ class MaterialsControllerTest < ActionController::TestCase
     assert_response :forbidden
   end
 
-  #EDIT TESTS
+  # EDIT TESTS
   test 'should not get edit page for not logged in users' do
-    #Not logged in = Redirect to login
+    # Not logged in = Redirect to login
     get :edit, params: { id: @material }
     assert_redirected_to new_user_session_path
   end
 
-  #logged in but insufficient permissions = ERROR
+  # logged in but insufficient permissions = ERROR
   test 'should get edit for material owner' do
     sign_in users(:regular_user)
     get :edit, params: { id: @material }
@@ -162,7 +162,7 @@ class MaterialsControllerTest < ActionController::TestCase
   end
 
   test 'should get edit for admin' do
-    #Owner of material logged in = SUCCESS
+    # Owner of material logged in = SUCCESS
     sign_in users(:admin)
     get :edit, params: { id: @material }
     assert_response :success
@@ -181,7 +181,7 @@ class MaterialsControllerTest < ActionController::TestCase
   end
 
   test 'should not get edit page for non-owner user' do
-    #Administrator = SUCCESS
+    # Administrator = SUCCESS
     sign_in users(:another_regular_user)
     get :edit, params: { id: @material }
     assert :forbidden
@@ -194,7 +194,7 @@ class MaterialsControllerTest < ActionController::TestCase
     assert_response :success
   end
 
-  #CREATE TEST
+  # CREATE TEST
   test 'should create material for user' do
     sign_in users(:regular_user)
     assert_difference('Material.count') do
@@ -268,8 +268,7 @@ class MaterialsControllerTest < ActionController::TestCase
       format: :json,
       material: { title: test_title,
                   url: test_url,
-                  content_provider_id: test_provider.id
-      }
+                  content_provider_id: test_provider.id }
     }
     assert_response :success
     assert_equal 'application/json; charset=utf-8', response.content_type, 'response content type not matched'
@@ -283,13 +282,13 @@ class MaterialsControllerTest < ActionController::TestCase
     assert_equal test_material.keywords, JSON.parse(response.body)['keywords'], 'keywords not matched'
     assert_equal test_material.status, JSON.parse(response.body)['status'], 'status not matched'
 
-    #optional attributes
+    # optional attributes
     assert_equal test_material.doi, JSON.parse(response.body)['doi'], 'doi not matched.'
     assert_equal test_provider.id, JSON.parse(response.body)['content_provider_id'], 'provider not matched'
     assert_equal test_material.resource_type, JSON.parse(response.body)['resource_type'], 'resource_type not matched'
     assert_equal test_material.version, JSON.parse(response.body)['version'], 'version not matched'
     assert_equal test_material.other_types, JSON.parse(response.body)['other_types'], 'other_types not matched'
-    #assert_equal test_material.events, JSON.parse(response.body)['events'], 'events not matched'
+    # assert_equal test_material.events, JSON.parse(response.body)['events'], 'events not matched'
     assert_equal test_material.target_audience, JSON.parse(response.body)['target_audience'], 'target audience not matched'
     assert_equal test_material.authors, JSON.parse(response.body)['authors'], 'authors not matched'
     assert_equal test_material.contributors, JSON.parse(response.body)['contributors'], 'contributors not matched'
@@ -350,7 +349,7 @@ class MaterialsControllerTest < ActionController::TestCase
     assert_redirected_to new_user_session_path
   end
 
-  #SHOW TEST
+  # SHOW TEST
   test 'should show material' do
     get :show, params: { id: @material }
     assert_response :success
@@ -421,7 +420,7 @@ class MaterialsControllerTest < ActionController::TestCase
     assert_equal material_url(assigns(:material), host: TeSS::Config.base_url), body['@id']
   end
 
-  #UPDATE TEST
+  # UPDATE TEST
   test 'should update material' do
     sign_in @material.user
     patch :update, params: { id: @material, material: @updated_material }
@@ -487,7 +486,7 @@ class MaterialsControllerTest < ActionController::TestCase
     assert_nil material.reload.edit_suggestion
   end
 
-  #DESTROY TEST
+  # DESTROY TEST
   test 'should destroy material owned by user' do
     sign_in users(:regular_user)
     assert_difference('Material.count', -1) do
@@ -540,26 +539,26 @@ class MaterialsControllerTest < ActionController::TestCase
     assert_redirected_to materials_path
   end
 
-  #CONTENT TESTS
-  #BREADCRUMBS
+  # CONTENT TESTS
+  # BREADCRUMBS
   test 'breadcrumbs for materials index' do
     get :index
     assert_response :success
-    assert_select 'div.breadcrumbs', :text => /Home/, :count => 1 do
-      assert_select 'a[href=?]', root_path, :count => 1
-      assert_select 'li[class=active]', :text => /Materials/, :count => 1
+    assert_select 'div.breadcrumbs', text: /Home/, count: 1 do
+      assert_select 'a[href=?]', root_path, count: 1
+      assert_select 'li[class=active]', text: /Materials/, count: 1
     end
   end
 
   test 'breadcrumbs for showing material' do
     get :show, params: { id: @material }
     assert_response :success
-    assert_select 'div.breadcrumbs', :text => /Home/, :count => 1 do
-      assert_select 'a[href=?]', root_path, :count => 1
-      assert_select 'li', :text => /Materials/, :count => 1 do
-        assert_select 'a[href=?]', materials_url, :count => 1
+    assert_select 'div.breadcrumbs', text: /Home/, count: 1 do
+      assert_select 'a[href=?]', root_path, count: 1
+      assert_select 'li', text: /Materials/, count: 1 do
+        assert_select 'a[href=?]', materials_url, count: 1
       end
-      assert_select 'li[class=active]', :text => /#{@material.title}/, :count => 1
+      assert_select 'li[class=active]', text: /#{@material.title}/, count: 1
     end
   end
 
@@ -567,15 +566,15 @@ class MaterialsControllerTest < ActionController::TestCase
     sign_in users(:regular_user)
     get :edit, params: { id: @material }
     assert_response :success
-    assert_select 'div.breadcrumbs', :text => /Home/, :count => 1 do
-      assert_select 'a[href=?]', root_path, :count => 1
-      assert_select 'li', :text => /Materials/, :count => 1 do
-        assert_select 'a[href=?]', materials_url, :count => 1
+    assert_select 'div.breadcrumbs', text: /Home/, count: 1 do
+      assert_select 'a[href=?]', root_path, count: 1
+      assert_select 'li', text: /Materials/, count: 1 do
+        assert_select 'a[href=?]', materials_url, count: 1
       end
-      assert_select 'li', :text => /#{@material.title}/, :count => 1 do
-        assert_select 'a[href=?]', material_url(@material), :count => 1
+      assert_select 'li', text: /#{@material.title}/, count: 1 do
+        assert_select 'a[href=?]', material_url(@material), count: 1
       end
-      assert_select 'li[class=active]', :text => /Edit/, :count => 1
+      assert_select 'li[class=active]', text: /Edit/, count: 1
     end
   end
 
@@ -583,66 +582,65 @@ class MaterialsControllerTest < ActionController::TestCase
     sign_in users(:regular_user)
     get :new
     assert_response :success
-    assert_select 'div.breadcrumbs', :text => /Home/, :count => 1 do
-      assert_select 'a[href=?]', root_path, :count => 1
-      assert_select 'li', :text => /Materials/, :count => 1 do
-        assert_select 'a[href=?]', materials_url, :count => 1
+    assert_select 'div.breadcrumbs', text: /Home/, count: 1 do
+      assert_select 'a[href=?]', root_path, count: 1
+      assert_select 'li', text: /Materials/, count: 1 do
+        assert_select 'a[href=?]', materials_url, count: 1
       end
-      assert_select 'li[class=active]', :text => /New/, :count => 1
+      assert_select 'li[class=active]', text: /New/, count: 1
     end
   end
 
-  #OTHER CONTENT
+  # OTHER CONTENT
 
   test 'material has correct layout' do
     get :show, params: { id: @material }
     assert_response :success
-    assert_select 'h2', :text => @material.title #Has Title
+    assert_select 'h2', text: @material.title # Has Title
     assert_select 'a.btn', text: 'View material', count: 1 do
       assert_select 'a[href=?]', @material.url, count: 1
     end
-    #Should not show when not logged in
-    assert_select 'a.btn[href=?]', edit_material_path(@material), :count => 0 #No Edit
-    assert_select 'a.btn[href=?]', material_path(@material), :count => 0 #No Edit
+    # Should not show when not logged in
+    assert_select 'a.btn[href=?]', edit_material_path(@material), count: 0 # No Edit
+    assert_select 'a.btn[href=?]', material_path(@material), count: 0 # No Edit
   end
 
   test 'do not show action buttons when not owner or admin' do
     sign_in users(:another_regular_user)
     get :show, params: { id: @material }
-    assert_select 'a.btn[href=?]', edit_material_path(@material), :count => 0 #No Edit
-    assert_select 'a.btn[href=?]', material_path(@material), :count => 0 #No Edit
+    assert_select 'a.btn[href=?]', edit_material_path(@material), count: 0 # No Edit
+    assert_select 'a.btn[href=?]', material_path(@material), count: 0 # No Edit
   end
 
   test 'show action buttons when owner' do
     sign_in users(:regular_user)
     get :show, params: { id: @material }
-    assert_select 'a.btn[href=?]', edit_material_path(@material), :count => 1
-    assert_select 'a.btn[href=?]', material_path(@material), :text => 'Delete', :count => 1
+    assert_select 'a.btn[href=?]', edit_material_path(@material), count: 1
+    assert_select 'a.btn[href=?]', material_path(@material), text: 'Delete', count: 1
   end
 
   test 'show action buttons when admin' do
     sign_in users(:admin)
     get :show, params: { id: @material }
-    assert_select 'a.btn[href=?]', edit_material_path(@material), :count => 1
-    assert_select 'a.btn[href=?]', material_path(@material), :text => 'Delete', :count => 1
+    assert_select 'a.btn[href=?]', edit_material_path(@material), count: 1
+    assert_select 'a.btn[href=?]', material_path(@material), text: 'Delete', count: 1
   end
 
   test 'show action buttons when approved editor' do
     @material.content_provider.add_editor users(:another_regular_user)
     sign_in users(:another_regular_user)
     get :show, params: { id: @material }
-    assert_select 'a.btn[href=?]', edit_material_path(@material), :count => 1
-    assert_select 'a.btn[href=?]', material_path(@material), :text => 'Delete', :count => 1
+    assert_select 'a.btn[href=?]', edit_material_path(@material), count: 1
+    assert_select 'a.btn[href=?]', material_path(@material), text: 'Delete', count: 1
   end
 
-  #API Actions
+  # API Actions
   test 'should find existing material by title and content provider' do
     post :check_exists, params: {
       format: :json,
       material: { title: @material.title,
                   url: 'whatever.com',
-                  content_provider_id: @material.content_provider_id
-      }
+                  content_provider_id: @material.content_provider_id }
     }
     assert_response :success
     assert_equal(JSON.parse(response.body)['id'], @material.id)
@@ -702,13 +700,13 @@ class MaterialsControllerTest < ActionController::TestCase
 
   test 'should display filters on index' do
     get :index
-    assert_select 'h4.nav-heading', :text => /Content provider/, :count => 0
-    assert_select 'li.masonry-brick', :count => Material.count
+    assert_select 'h4.nav-heading', text: /Content provider/, count: 0
+    assert_select 'li.masonry-brick', count: Material.count
   end
 
   test 'should create new material through API' do
     scraper_role = Role.fetch('scraper_user')
-    scraper_user = User.where(:role_id => scraper_role.id).first
+    scraper_user = User.where(role_id: scraper_role.id).first
     material_title = 'horse'
     assert scraper_user
     assert_difference('Material.count') do
@@ -722,7 +720,7 @@ class MaterialsControllerTest < ActionController::TestCase
           contact: 'default contact',
           doi: 'https://doi.org/10.1001/RSE.2.190',
           licence: 'CC-BY-4.0',
-          keywords: ['scraped', 'through', 'api'],
+          keywords: %w[scraped through api],
           status: 'active'
         },
         format: 'json'
@@ -733,7 +731,7 @@ class MaterialsControllerTest < ActionController::TestCase
 
   test 'should not create new material without valid authentication token' do
     scraper_role = Role.fetch('scraper_user')
-    scraper_user = User.where(:role_id => scraper_role.id).first
+    scraper_user = User.where(role_id: scraper_role.id).first
     assert scraper_user
 
     assert_no_difference('Material.count') do
@@ -747,7 +745,7 @@ class MaterialsControllerTest < ActionController::TestCase
           contact: 'default contact',
           doi: 'https://doi.org/10.1001/RSE.2.190',
           licence: 'CC-BY-4.0',
-          keywords: %{ invalid authtoken },
+          keywords: %( invalid authtoken ),
           status: 'active'
         },
         format: 'json'
@@ -760,7 +758,7 @@ class MaterialsControllerTest < ActionController::TestCase
     user = users(:scraper_user)
     material = materials(:scraper_user_material)
 
-    new_title = "totally new title"
+    new_title = 'totally new title'
     assert_no_difference('Material.count') do
       patch :update, params: {
         user_token: user.authentication_token,
@@ -783,7 +781,7 @@ class MaterialsControllerTest < ActionController::TestCase
     other_user = users(:another_regular_user)
     material = user.materials.first
 
-    new_title = "totally new title"
+    new_title = 'totally new title'
     assert_no_difference('Material.count') do
       patch :update, params: {
         user_token: other_user.authentication_token,
@@ -848,7 +846,7 @@ class MaterialsControllerTest < ActionController::TestCase
           description: 'New description',
           url: 'http://new.url.com',
           content_provider_id: ContentProvider.first.id,
-          external_resources_attributes: { "1" => { title: 'Cool link', url: 'https://tess.elixir-uk.org/', _destroy: '0' } }
+          external_resources_attributes: { '1' => { title: 'Cool link', url: 'https://tess.elixir-uk.org/', _destroy: '0' } }
         }
       }
     end
@@ -873,7 +871,7 @@ class MaterialsControllerTest < ActionController::TestCase
           description: 'New description',
           url: 'http://new.url.com',
           content_provider_id: ContentProvider.first.id,
-          external_resources_attributes: { "0" => { id: resource.id, _destroy: '1' } }
+          external_resources_attributes: { '0' => { id: resource.id, _destroy: '1' } }
         }
       }
     end
@@ -895,7 +893,7 @@ class MaterialsControllerTest < ActionController::TestCase
           description: 'New description',
           url: 'http://new.url.com',
           content_provider_id: ContentProvider.first.id,
-          external_resources_attributes: { "1" => { id: resource.id, title: 'Cool link',
+          external_resources_attributes: { '1' => { id: resource.id, title: 'Cool link',
                                                     url: 'http://www.reddit.com', _destroy: '0' } }
         }
       }
@@ -907,19 +905,17 @@ class MaterialsControllerTest < ActionController::TestCase
   end
 
   # TODO: SOLR tests will not run on TRAVIS. Explore stratergy for testing solr
-=begin
-      test 'should return matching materials' do
-        get 'index', :format => :json, :q => 'training'
-        assert_response :success
-        assert response.body.size > 0
-      end
-
-      test 'should return no matching materials' do
-        get 'index', :format => :json, :q => 'kdfsajfklasdjfljsdfljdsfjncvmn'
-        assert_response :success
-        assert_equal(response.body,'[]')
-        end
-=end
+  #       test 'should return matching materials' do
+  #         get 'index', :format => :json, :q => 'training'
+  #         assert_response :success
+  #         assert response.body.size > 0
+  #       end
+  #
+  #       test 'should return no matching materials' do
+  #         get 'index', :format => :json, :q => 'kdfsajfklasdjfljsdfljdsfjncvmn'
+  #         assert_response :success
+  #         assert_equal(response.body,'[]')
+  #         end
   test 'finds multiple preferred labels' do
     topic_one = Edam::Ontology.instance.lookup('http://edamontology.org/topic_0154')
     topic_two = Edam::Ontology.instance.lookup('http://edamontology.org/topic_0078')
@@ -966,10 +962,9 @@ class MaterialsControllerTest < ActionController::TestCase
                     url: 'http://www.example.com/sanity/0',
                     doi: 'https://doi.org/10.1100/RSE.2019.23',
                     licence: 'CC-BY-4.0',
-                    keywords: ['insanity', 'sanitized', 'sanitary'],
+                    keywords: %w[insanity sanitized sanitary],
                     contact: 'default contact',
-                    status: 'development'
-        }
+                    status: 'development' }
       }
     end
 
@@ -1075,7 +1070,7 @@ class MaterialsControllerTest < ActionController::TestCase
   test 'can lock fields' do
     sign_in @material.user
     assert_difference('FieldLock.count', 2) do
-      patch :update, params: { id: @material, material: { title: 'hi', locked_fields: ['title', 'description'] } }
+      patch :update, params: { id: @material, material: { title: 'hi', locked_fields: %w[title description] } }
     end
 
     assert_redirected_to material_path(assigns(:material))
@@ -1254,10 +1249,9 @@ class MaterialsControllerTest < ActionController::TestCase
                       url: 'http://example.com/dodgy-event',
                       doi: 'https://doi.org/10.10067/SEA.2019.22',
                       licence: 'CC-BY-4.0',
-                      keywords: %w{ dodgy event },
+                      keywords: %w[dodgy event],
                       contact: 'default contact',
-                      status: 'archived'
-          }
+                      status: 'archived' }
         }
       end
     end
@@ -1272,7 +1266,7 @@ class MaterialsControllerTest < ActionController::TestCase
                                               title: @material.title, url: 'http://example.com/dodgy-event',
                                               doi: 'https://doi.org/10.10067/SEA.2019.22', status: 'active',
                                               licence: 'CC-BY-4.0', contact: 'default contact',
-                                              keywords: %w{ dodgy event unverified user })
+                                              keywords: %w[dodgy event unverified user])
 
     assert_enqueued_jobs 0 do
       assert_difference('Material.count') do
@@ -1281,8 +1275,7 @@ class MaterialsControllerTest < ActionController::TestCase
                       title: @material.title, url: 'http://example.com/dodgy-event-2',
                       licence: 'CC-BY-4.0', contact: 'default contact', status: 'active',
                       doi: 'https://doi.org/10.10067/SEA.2019.22',
-                      keywords: %w{ another dodgy event }
-          }
+                      keywords: %w[another dodgy event] }
         }
       end
     end
@@ -1322,7 +1315,7 @@ class MaterialsControllerTest < ActionController::TestCase
           contact: 'default contact',
           doi: 'https://doi.org/10.1001/RSE.2.190',
           licence: 'CC-BY-4.0',
-          keywords: ['scraped', 'through', 'api'],
+          keywords: %w[scraped through api],
           status: 'active'
         },
         format: 'json'
@@ -1395,11 +1388,11 @@ class MaterialsControllerTest < ActionController::TestCase
   end
 
   test 'should hide fields' do
-    with_settings(feature: { materials_disabled: ['licence', 'scientific_topics', 'resource_type'] }) do
+    with_settings(feature: { materials_disabled: %w[licence scientific_topics resource_type] }) do
       sign_in users(:regular_user)
       get :new
       assert_response :success
-      assert_select 'div.hidden' do |div|
+      assert_select 'div.hidden' do |_div|
         assert_select 'label', text: 'Licence', count: 1
         assert_select 'label', text: 'Status', count: 0
       end
@@ -1435,8 +1428,7 @@ class MaterialsControllerTest < ActionController::TestCase
                                              description: 'hey',
                                              external_resources_attributes: [
                                                { title: 'A tool perhaps', url: 'https://bio.tools/some_tool' }
-                                             ]
-        }}
+                                             ] } }
 
         assert_response :success
         assert_select 'h2', text: 'Potential material'
@@ -1460,10 +1452,10 @@ class MaterialsControllerTest < ActionController::TestCase
   test 'should show unverified users material to themselves' do
     sign_in users(:unverified_user)
     material = users(:unverified_user).materials.create!(description: @material.description,
-                                              title: @material.title, url: 'http://example.com/dodgy-event',
-                                              doi: 'https://doi.org/10.10067/SEA.2019.22', status: 'active',
-                                              licence: 'CC-BY-4.0', contact: 'default contact',
-                                              keywords: %w{ dodgy event unverified user })
+                                                         title: @material.title, url: 'http://example.com/dodgy-event',
+                                                         doi: 'https://doi.org/10.10067/SEA.2019.22', status: 'active',
+                                                         licence: 'CC-BY-4.0', contact: 'default contact',
+                                                         keywords: %w[dodgy event unverified user])
 
     get :show, params: { id: material }
 
@@ -1474,10 +1466,10 @@ class MaterialsControllerTest < ActionController::TestCase
 
   test 'should show unverified users material to admin' do
     material = users(:unverified_user).materials.create!(description: @material.description,
-                                              title: @material.title, url: 'http://example.com/dodgy-event',
-                                              doi: 'https://doi.org/10.10067/SEA.2019.22', status: 'active',
-                                              licence: 'CC-BY-4.0', contact: 'default contact',
-                                              keywords: %w{ dodgy event unverified user })
+                                                         title: @material.title, url: 'http://example.com/dodgy-event',
+                                                         doi: 'https://doi.org/10.10067/SEA.2019.22', status: 'active',
+                                                         licence: 'CC-BY-4.0', contact: 'default contact',
+                                                         keywords: %w[dodgy event unverified user])
     sign_in users(:admin)
 
     get :show, params: { id: material }
@@ -1489,10 +1481,10 @@ class MaterialsControllerTest < ActionController::TestCase
 
   test 'should not show unverified users material anon user' do
     material = users(:unverified_user).materials.create!(description: @material.description,
-                                              title: @material.title, url: 'http://example.com/dodgy-event',
-                                              doi: 'https://doi.org/10.10067/SEA.2019.22', status: 'active',
-                                              licence: 'CC-BY-4.0', contact: 'default contact',
-                                              keywords: %w{ dodgy event unverified user })
+                                                         title: @material.title, url: 'http://example.com/dodgy-event',
+                                                         doi: 'https://doi.org/10.10067/SEA.2019.22', status: 'active',
+                                                         licence: 'CC-BY-4.0', contact: 'default contact',
+                                                         keywords: %w[dodgy event unverified user])
 
     get :show, params: { id: material }
     assert_response :forbidden
@@ -1604,4 +1596,16 @@ class MaterialsControllerTest < ActionController::TestCase
       assert_equal plant_space, assigns(:material).space
     end
   end
+
+  test 'should render scientific topics and operations as links in extra metadata' do
+    @material.scientific_topic_uris = ['http://edamontology.org/topic_0622'] # Genomics
+    @material.operation_uris = ['http://edamontology.org/operation_0292'] # Sequence alignment
+    @material.save!
+
+    get :show, params: { id: @material }
+    assert_response :success
+
+    assert_select 'p.scientific_topics a[href="http://edamontology.org/topic_0622"]', text: 'Genomics'
+    assert_select 'p.operations a[href="http://edamontology.org/operation_0292"]', text: 'Sequence alignment'
+  end
 end
diff --git a/test/controllers/stars_controller_test.rb b/test/controllers/stars_controller_test.rb
index 49762dfe6..f54365ce8 100644
--- a/test/controllers/stars_controller_test.rb
+++ b/test/controllers/stars_controller_test.rb
@@ -1,10 +1,9 @@
 require 'test_helper'
 
 class StarsControllerTest < ActionController::TestCase
-
   include Devise::Test::ControllerHelpers
 
-  test "can star a resource" do
+  test 'can star a resource' do
     sign_in users(:regular_user)
     material = materials(:good_material)
 
@@ -15,7 +14,7 @@ class StarsControllerTest < ActionController::TestCase
     assert_response :success
   end
 
-  test "does not add duplicate star to resource" do
+  test 'does not add duplicate star to resource' do
     user = users(:regular_user)
     sign_in user
     material = materials(:good_material)
@@ -28,7 +27,7 @@ class StarsControllerTest < ActionController::TestCase
     assert_response :success
   end
 
-  test "can un-star resource" do
+  test 'can un-star resource' do
     user = users(:regular_user)
     sign_in user
     material = materials(:good_material)
@@ -41,7 +40,7 @@ class StarsControllerTest < ActionController::TestCase
     assert_response :success
   end
 
-  test "cannot star a resource if not logged in" do
+  test 'cannot star a resource if not logged in' do
     material = materials(:good_material)
 
     assert_no_difference('Star.count') do
@@ -51,7 +50,7 @@ class StarsControllerTest < ActionController::TestCase
     assert_response :unauthorized
   end
 
-  test "cannot create bad star" do
+  test 'cannot create bad star' do
     user = users(:regular_user)
     sign_in user
 
@@ -62,7 +61,7 @@ class StarsControllerTest < ActionController::TestCase
     assert_response :unprocessable_entity
   end
 
-  test "can view list of stars" do
+  test 'can view list of stars' do
     user = users(:regular_user)
     sign_in user
     material = materials(:good_material)
@@ -71,7 +70,7 @@ class StarsControllerTest < ActionController::TestCase
     get :index
 
     assert_response :success
-    assert_select '#materials div.search-results-count', text: "1 Material", count: 1
+    assert_select '#materials div.search-results-count', text: '1 Material', count: 1
     assert_select '#materials li.masonry-brick a.link-overlay[href=?]', material_path(material), count: 1
   end
 end
diff --git a/test/helpers/materials_helper_test.rb b/test/helpers/materials_helper_test.rb
index 91a6c3f0a..f348b4fd1 100644
--- a/test/helpers/materials_helper_test.rb
+++ b/test/helpers/materials_helper_test.rb
@@ -1,12 +1,46 @@
 require 'test_helper'
 
 class MaterialsHelperTest < ActionView::TestCase
-
-  test "edam file loaded successfully" do
+  test 'edam file loaded successfully' do
     topics = scientific_topic_names_for_autocomplete
     assert_equal topics.class, Array
     assert_not_empty topics
     assert_includes topics, 'Metabolomics'
   end
 
+  test 'keywords_and_topics generates spans with css classes for scientific topics and operations' do
+    topic_term = OpenStruct.new(preferred_label: 'Genomics', uri: 'http://edamontology.org/topic_0622')
+    operation_term = OpenStruct.new(preferred_label: 'Sequence alignment', uri: 'http://edamontology.org/operation_0292')
+    resource = OpenStruct.new(
+      scientific_topics: [topic_term],
+      operations: [operation_term],
+      keywords: %w[keyword1 keyword2]
+    )
+    result = keywords_and_topics(resource)
+
+    assert_includes result, 'Genomics'
+    assert_includes result, 'tag-topic'
+    assert_includes result, 'Sequence alignment'
+    assert_includes result, 'tag-operation'
+    assert_includes result, 'keyword1'
+    assert_includes result, 'keyword2'
+  end
+
+  test 'keywords_and_topics handles missing attributes' do
+    resource = OpenStruct.new
+
+    result = keywords_and_topics(resource)
+    assert_equal '', result
+  end
+
+  test 'keywords_and_topics with limit' do
+    topic_term = OpenStruct.new(preferred_label: 'Genomics', uri: 'http://edamontology.org/topic_0622')
+    resource = OpenStruct.new(
+      scientific_topics: [topic_term],
+      keywords: %w[keyword1 keyword2 keyword3]
+    )
+    result = keywords_and_topics(resource, limit: 2)
+
+    assert_includes result, '&hellip;'
+  end
 end