diff --git a/tests/playground.html b/tests/playground.html
index 96a5fa85d..48674ec72 100644
--- a/tests/playground.html
+++ b/tests/playground.html
@@ -67,6 +67,7 @@
 <script src="blocks/test_blocks.js"></script>
 <script src="themes/test_themes.js"></script>
 <script src="./playgrounds/screenshot.js"></script>
+<script src="./playgrounds/test_blocks_toolbox.js"></script>
 
 <script>
 // Custom requires for the playground.
@@ -95,14 +96,7 @@ function start() {
   var rtl = match && match[1] == 'rtl';
   document.forms.options.elements.dir.selectedIndex = Number(rtl);
   var toolbox = getToolboxElement();
-  var toolboxNames = [
-      'toolbox-categories',
-      'toolbox-categories-typed-variables',
-      'toolbox-simple',
-      'toolbox-test-blocks'
-  ];
-  document.forms.options.elements.toolbox.selectedIndex =
-      toolboxNames.indexOf(toolbox.id);
+  setToolboxDropdown();
   match = location.search.match(/side=([^&]+)/);
   var autoimport = !!location.search.match(/autoimport=([^&]+)/);
   // Create main workspace.
@@ -295,16 +289,36 @@ function setBackgroundColour() {
   }
 }
 
-function getToolboxElement() {
+function getToolboxSuffix() {
   var match = location.search.match(/toolbox=([^&]+)/);
   // Default to the basic toolbox with categories and untyped variables,
   // but override that if the toolbox type is set in the URL.
-  var toolboxSuffix = (match ? match[1] : 'categories');
-  // The three possible values are: "simple", "categories",
-  // "categories-typed-variables".
+  return (match ? match[1] : 'categories');
+}
+
+function getToolboxElement() {
+  // The four possible values are: "simple", "categories",
+  // "categories-typed-variables", and "test-blocks".
+  var toolboxSuffix = getToolboxSuffix();
+  // test-blocks are defined in JSON
+  if (toolboxSuffix == 'test-blocks') {
+    return testBlocksToolbox;
+  }
   return document.getElementById('toolbox-' + toolboxSuffix);
 }
 
+function setToolboxDropdown() {
+  var toolboxNames = [
+      'toolbox-categories',
+      'toolbox-categories-typed-variables',
+      'toolbox-simple',
+      'toolbox-test-blocks'
+  ];
+  var toolboxSuffix = getToolboxSuffix();
+  document.forms.options.elements.toolbox.selectedIndex =
+      toolboxNames.indexOf('toolbox-' + toolboxSuffix);
+}
+
 function toXml() {
   var output = document.getElementById('importExport');
   var xml = Blockly.Xml.workspaceToDom(workspace);
@@ -1282,362 +1296,5 @@ var spaghettiXml = [
     <category name="Variables" categorystyle="variable_category" custom="VARIABLE_DYNAMIC"></category>
     <category name="Functions" categorystyle="procedure_category" custom="PROCEDURE"></category>
   </xml>
-
-  <!-- toolbox-test-blocks has a category menu and an auto-closing flyout.
-  The blocks in this toolbox reflect block configurations not used by
-  the standard predefined blocks, and so test alternative block rendering
-  code paths. -->
-  <xml xmlns="https://developers.google.com/blockly/xml" id="toolbox-test-blocks" style="display: none">
-    <category name="Align">
-      <block type="test_align_dummy_right"></block>
-      <block type="test_align_all"></block>
-      <block type="test_align_with_external_input"></block>
-    </category>
-    <category name="Basic">
-      <block type="test_basic_empty"></block>
-      <block type="test_basic_empty_with_mutator"></block>
-      <block type="test_basic_dummy"></block>
-      <block type="test_basic_multiple_dummy"></block>
-      <block type="test_basic_stack"></block>
-      <block type="test_basic_row"></block>
-      <block type="test_basic_value_to_stack"></block>
-      <block type="test_basic_value_to_statement"></block>
-      <block type="test_basic_limit_instances"></block>
-      <block type="test_basic_tooltips"></block>
-      <block type="test_basic_javascript"></block>
-    </category>
-    <category name="Connections" expanded="true">
-      <category name="Row">
-        <label text="blocks have"></label>
-        <sep gap="-1"></sep>
-        <label text="tooltips"></label>
-
-        <button text="insert" callbackkey="insertConnectionRows"></button>
-        <sep gap="7"></sep>
-        <block type="test_connections_row_input"></block>
-        <sep gap="7"></sep>
-        <block type="test_connections_row_blue"></block>
-        <sep gap="7"></sep>
-        <block type="test_connections_row_yellow"></block>
-        <sep gap="7"></sep>
-        <block type="test_connections_row_red"></block>
-        <sep gap="7"></sep>
-        <block type="test_connections_row_output"></block>
-        <block type="test_connections_row_yellow">
-          <value name="NAME">
-            <block type="test_connections_row_yellow" movable="false"></block>
-          </value>
-        </block>
-        <sep gap="7"></sep>
-        <block type="test_connections_multivalue_1valid"></block>
-        <sep gap="7"></sep>
-        <block type="test_connections_multivalue_2valid"></block>
-      </category>
-      <category name="Stack">
-        <label text="blocks have"></label>
-        <sep gap="-1"></sep>
-        <label text="tooltips"></label>
-
-        <button text="insert" callbackkey="insertConnectionStacks"></button>
-        <sep gap="7"></sep>
-        <block type="test_connections_stack_next"></block>
-        <sep gap="7"></sep>
-        <block type="test_connections_stack_blue"></block>
-        <sep gap="7"></sep>
-        <block type="test_connections_stack_yellow"></block>
-        <sep gap="7"></sep>
-        <block type="test_connections_stack_red"></block>
-        <sep gap="7"></sep>
-        <block type="test_connections_stack_prev"></block>
-        <block type="test_connections_stack_yellow">
-          <next>
-            <block type="test_connections_stack_yellow" movable="false"></block>
-          </next>
-        </block>
-      </category>
-      <category name="Statement">
-        <label text="blocks have"></label>
-        <sep gap="-1"></sep>
-        <label text="tooltips"></label>
-
-        <button text="insert" callbackkey="insertConnectionStatements"></button>
-        <sep gap="7"></sep>
-        <block type="test_connections_statement_blue"></block>
-        <sep gap="7"></sep>
-        <block type="test_connections_statement_yellow"></block>
-        <sep gap="7"></sep>
-        <block type="test_connections_statement_red"></block>
-        <block type="test_connections_statement_nonext"></block>
-        <sep gap="7"></sep>
-        <block type="test_connections_multistatement_1valid"></block>
-        <sep gap="7"></sep>
-        <block type="test_connections_multistatement_2valid"></block>
-      </category>
-    </category>
-    <category name="Drag">
-      <label text="Drag each to the workspace"></label>
-      <block type="text_print">
-        <value name="TEXT">
-          <block type="text">
-            <field name="TEXT">Drag me by this child</field>
-          </block>
-        </value>
-      </block>
-      <block type="text_print">
-        <value name="TEXT">
-          <shadow type="text">
-            <field name="TEXT">Drag me by this shadow</field>
-          </shadow>
-        </value>
-      </block>
-      <block type="text_print">
-        <value name="TEXT">
-          <shadow type="text">
-            <field name="TEXT">Shadow value</field>
-          </shadow>
-        </value>
-        <next>
-          <shadow type="text_print">
-            <value name="TEXT">
-              <shadow type="text">
-                <field name="TEXT">Shadow statement</field>
-              </shadow>
-            </value>
-          </shadow>
-        </next>
-      </block>
-      <label text="Multiple Variable Refs"></label>
-      <block type="text_print">
-        <value name="TEXT">
-          <block type="variables_get">
-            <field name="VAR" id="item">item</field>
-          </block>
-        </value>
-        <next>
-          <block type="text_print">
-            <value name="TEXT">
-              <block type="variables_get">
-                <field name="VAR" id="item">item</field>
-              </block>
-            </value>
-          </block>
-        </next>
-      </block>
-      <label text="Procedure Definitions"></label>
-      <block type="procedures_defnoreturn">
-        <field name="NAME">without arguments</field>
-        <statement name="STACK">
-          <block type="text_print">
-            <value name="TEXT">
-              <shadow type="text">
-                <field name="TEXT">No argument reference.</field>
-              </shadow>
-            </value>
-          </block>
-        </statement>
-      </block>
-      <block type="procedures_defnoreturn">
-        <mutation>
-          <arg name="fnArgument"></arg>
-        </mutation>
-        <field name="NAME">with one argument</field>
-        <statement name="STACK">
-          <block type="text_print">
-            <value name="TEXT">
-              <shadow type="text">
-                <field name="TEXT">Expected an argument reference here.</field>
-              </shadow>
-              <block type="variables_get">
-                <field name="VAR">fnArgument</field>
-              </block>
-            </value>
-          </block>
-        </statement>
-      </block>
-    </category>
-    <category name="Fields" expanded="true">
-      <category name="Defaults">
-        <button text="add blocks to workspace" callbackKey="addAllBlocksToWorkspace"></button>
-        <sep gap="8"></sep>
-        <button text="set random style" callbackKey="setRandomStyle"></button>
-        <sep gap="8"></sep>
-        <button text="toggle enabled" callbackKey="toggleEnabled"></button>
-        <sep gap="8"></sep>
-        <button text="toggle shadow" callbackKey="toggleShadow"></button>
-        <sep gap="8"></sep>
-        <button text="toggle collapsed" callbackKey="toggleCollapsed"></button>
-        <block type="test_fields_angle"></block>
-        <block type="test_fields_checkbox"></block>
-        <block type="test_fields_colour"></block>
-        <block type="test_fields_colour_options"></block>
-        <block type="test_fields_text_input"></block>
-        <block type="test_fields_only_text_input"></block>
-        <block type="test_fields_multilinetext"></block>
-        <block type="test_fields_variable"></block>
-        <button text="randomize label text" callbackKey="randomizeLabelText"></button>
-        <sep gap="12"></sep>
-        <block type="test_fields_label_serializable"></block>
-        <button text="change image" callbackKey="changeImage"></button>
-        <sep gap="12"></sep>
-        <block type="test_fields_image"></block>
-      </category>
-      <category name="Numbers">
-        <block type="test_numbers_float">
-          <field name="NUM">123.456</field>
-        </block>
-        <block type="test_numbers_hundredths">
-          <field name="NUM">123.456</field>
-        </block>
-        <block type="test_numbers_halves">
-          <field name="NUM">123.456</field>
-        </block>
-        <block type="test_numbers_whole">
-          <field name="NUM">123.456</field>
-        </block>
-        <block type="test_numbers_three_halves">
-          <field name="NUM">123.456</field>
-        </block>
-        <block type="test_numbers_whole_bounded">
-          <field name="NOTE">60</field>
-        </block>
-      </category>
-      <category name="Angles">
-        <block type="test_angles_clockwise"></block>
-        <block type="test_angles_offset"></block>
-        <block type="test_angles_wrap"></block>
-        <block type="test_angles_round_30"></block>
-        <block type="test_angles_round_0"></block>
-        <block type="test_angles_protractor"></block>
-        <block type="test_angles_compass"></block>
-      </category>
-      <category name="Drop-downs">
-        <label text="Dynamic"></label>
-        <block type="test_dropdowns_dynamic"></block>
-        <button text="Add option" callbackKey="addDynamicOption"></button>
-        <button text="Remove option" callbackKey="removeDynamicOption"></button>
-        <block type="test_dropdowns_dynamic_random"></block>
-        <label text="Other"></label>
-        <block type="test_dropdowns_long"></block>
-        <block type="test_dropdowns_images"></block>
-        <block type="test_dropdowns_images_and_text"></block>
-      </category>
-      <category name="Images">
-        <block type="test_images_datauri"></block>
-        <block type="test_images_small"></block>
-        <block type="test_images_large"></block>
-        <block type="test_images_fliprtl"></block>
-        <block type="test_images_missing"></block>
-        <block type="test_images_many_icons"></block>
-        <block type="test_images_clickhandler"></block>
-      </category>
-      <category name="Emoji! o((*^ᴗ^*))o">
-        <label text="Unicode & Emojis"></label>
-        <block type="test_style_emoji"></block>
-        <block type="text">
-          <field name="TEXT">Robot face in text field: &#x1f916;</field>
-        </block>
-        <block type="text">
-          <field name="TEXT">Zalgo in text field: B&#776;&#788;&#862;&#795;&#842;&#827;&#806;&#837;&#812;&#792;&#816;&#846;&#805;l&#771;&#832;&#833;&#864;&#849;&#849;&#789;&#861;&#801;&#854;&#863;&#811;&#826;&#812;&#790;&#803;&#819;o&#843;&#777;&#778;&#785;&#831;&#829;&#794;&#825;&#857;&#814;&#802;&#811;&#852;c&#843;&#786;&#849;&#778;&#861;&#775;&#825;&#825;&#796;&#857;&#825;&#800;&#824;k&#778;&#850;&#833;&#774;&#772;&#782;&#862;&#770;&#789;&#788;&#841;&#801;&#811;&#860;&#839;&#790;&#819;&#854;l&#832;&#774;&#836;&#831;&#776;&#787;&#855;&#816;&#793;&#798;&#819;&#809;&#800;&#854;&#815;y&#864;&#783;&#856;&#773;&#832;&#808;&#799;&#839;&#814;&#840;&#812;&#793;&#818;&#801;</field>
-        </block>
-      </category>
-      <category name="Validators">
-        <button text="add blocks to workspace" callbackKey="addAllBlocksToWorkspace"></button>
-        <sep gap="8"></sep>
-        <button text="set input" callbackKey="setInput"></button>
-        <label text="Dispose block"></label>
-        <sep gap="12"></sep>
-        <block type="test_validators_dispose_block"></block>
-        <label text="Angles"></label>
-        <sep gap="12"></sep>
-        <block type="test_validators_angle_null"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_angle_mult30_force"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_angle_mult30_null"></block>
-        <label text="Checkboxes"></label>
-        <sep gap="12"></sep>
-        <block type="test_validators_checkbox_null"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_checkbox_match"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_checkbox_not_match_null"></block>
-        <label text="Colours"></label>
-        <sep gap="12"></sep>
-        <block type="test_validators_colour_null"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_colour_force_red"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_colour_red_null"></block>
-        <label text="Dropdowns"></label>
-        <sep gap="12"></sep>
-        <block type="test_validators_dropdown_null"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_dropdown_force_1s"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_dropdown_1s_null"></block>
-        <label text="Numbers"></label>
-        <sep gap="12"></sep>
-        <block type="test_validators_number_null"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_number_mult10_force"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_number_mult10_null"></block>
-        <label text="Text"></label>
-        <sep gap="12"></sep>
-        <block type="test_validators_text_null"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_text_A"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_text_B"></block>
-        <label text="Variables"></label>
-        <sep gap="8"></sep>
-        <button text="add test variables" callbackKey="addVariables" web-class="modifiesWorkspace"></button>
-        <sep gap="12"></sep>
-        <block type="test_validators_variable_null"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_variable_force_1s"></block>
-        <sep gap="12"></sep>
-        <block type="test_validators_variable_1s_null"></block>
-      </category>
-    </category>
-    <category name="Mutators">
-      <label text="logic_compare"></label>
-      <block type="logic_compare">
-        <value name="A">
-          <shadow type="math_number">
-            <field name="NUM">10</field>
-          </shadow>
-        </value>
-        <value name="B">
-          <shadow type="math_number">
-            <field name="NUM">10</field>
-          </shadow>
-        </value>
-      </block>
-      <block type="logic_compare">
-        <value name="A">
-          <block type="math_number">
-            <field name="NUM">10</field>
-          </block>
-        </value>
-        <value name="B">
-          <block type="math_number">
-            <field name="NUM">10</field>
-          </block>
-        </value>
-      </block>
-    </category>
-    <category name="Style">
-      <label text="Hats"></label>
-      <block type="test_style_hat"></block>
-      <label text="Colour"></label>
-      <block type="test_style_hex1"></block>
-      <block type="test_style_hex2"></block>
-      <block type="test_style_hex3"></block>
-      <block type="test_style_no_colour"></block>
-      <block type="test_style_hex4"></block>
-      <block type="test_style_hex5"></block>
-    </category>
-  </xml>
 </body>
 </html>
diff --git a/tests/playgrounds/test_blocks_toolbox.js b/tests/playgrounds/test_blocks_toolbox.js
new file mode 100644
index 000000000..2a1a6a90f
--- /dev/null
+++ b/tests/playgrounds/test_blocks_toolbox.js
@@ -0,0 +1,956 @@
+/**
+ * @license
+ * Copyright 2020 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @fileoverview Test blocks toolbox has a category menu and an auto-closing flyout.
+ * The blocks in this toolbox reflect block configurations not used by
+ * the standard predefined blocks, and so test alternative block rendering
+ * code paths.
+ * @author aschmiedt@google.com (Abby Schmiedt)
+ */
+
+
+var alignCategory = {
+  "kind": "CATEGORY",
+  "name": "Align",
+  "contents": [
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_align_dummy_right\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_align_all\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_align_with_external_input\"></block>",
+    }
+  ],
+};
+
+var basicCategory = {
+  "kind": "CATEGORY",
+  "name": "Basic",
+  "contents": [
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_basic_empty\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_basic_empty_with_mutator\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_basic_dummy\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_basic_multiple_dummy\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_basic_stack\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_basic_row\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_basic_value_to_stack\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_basic_value_to_statement\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_basic_limit_instances\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_basic_tooltips\"></block>"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_basic_javascript\"></block>",
+    }
+  ],
+};
+
+var rowCategory = {
+  "kind": "CATEGORY",
+  "name": "Row",
+  "contents": [
+    {
+      "kind": "LABEL",
+      "text": "blocks have"
+    },
+    {
+      "kind": "SEP",
+      "gap": "-1"
+    },
+    {
+      "kind": "LABEL",
+      "text": "tooltips"
+    },
+    {
+      "kind": "BUTTON",
+      "text": "insert",
+      "callbackkey": "insertConnectionRows"
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_row_input\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_row_blue\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_row_yellow\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_row_red\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_row_output\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_row_yellow\"><value name=\"NAME\"><block type=\"test_connections_row_yellow\" movable=\"false\"></block></value></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_multivalue_1valid\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_multivalue_2valid\"></block>",
+    }
+  ],
+};
+
+var stackCategory = {
+  "kind": "CATEGORY",
+  "name": "Stack",
+  "contents": [
+    {
+      "kind": "LABEL",
+      "text": "blocks have"
+    },
+    {
+      "kind": "SEP",
+      "gap": "-1"
+    },
+    {
+      "kind": "LABEL",
+      "text": "tooltips"
+    },
+    {
+      "kind": "BUTTON",
+      "text": "insert",
+      "callbackkey": "insertConnectionStacks"
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_stack_next\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_stack_blue\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_stack_yellow\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_stack_red\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_stack_prev\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_stack_yellow\"><next><block type=\"test_connections_stack_yellow\" movable=\"false\"></block></next></block>",
+    }
+  ],
+};
+
+var statementCategory = {
+  "kind": "CATEGORY",
+  "name": "Statement",
+  "contents": [
+    {
+      "kind": "LABEL",
+      "text": "blocks have"
+    },
+    {
+      "kind": "SEP",
+      "gap": "-1"
+    },
+    {
+      "kind": "LABEL",
+      "text": "tooltips"
+    },
+    {
+      "kind": "BUTTON",
+      "text": "insert",
+      "callbackkey": "insertConnectionStatements"
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_statement_blue\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_statement_yellow\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_statement_red\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_statement_nonext\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_multistatement_1valid\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "7"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_connections_multistatement_2valid\"></block>",
+    }
+  ],
+};
+
+var dragCategory = {
+  "kind": "CATEGORY",
+  "name": "Drag",
+  "contents": [
+    {
+      "kind": "LABEL",
+      "text": "Drag each to the workspace"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"text_print\"><value name=\"TEXT\"><block type=\"text\"><field name=\"TEXT\">Dragmebythischild</field></block></value></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"text_print\"><value name=\"TEXT\"><shadow type=\"text\"><field name=\"TEXT\">Dragmebythisshadow</field></shadow></value></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"text_print\"><value name=\"TEXT\"><shadow type=\"text\"><field name=\"TEXT\">Shadowvalue</field></shadow></value><next><shadow type=\"text_print\"><value name=\"TEXT\"><shadow type=\"text\"><field name=\"TEXT\">Shadowstatement</field></shadow></value></shadow></next></block>",
+    },
+    {
+      "kind": "LABEL",
+      "text": "Multiple Variable Refs"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"text_print\"><value name=\"TEXT\"><block type=\"variables_get\"><field name=\"VAR\" id=\"item\">item</field></block></value><next><block type=\"text_print\"><value name=\"TEXT\"><block type=\"variables_get\"><field name=\"VAR\" id=\"item\">item</field></block></value></block></next></block>",
+    },
+    {
+      "kind": "LABEL",
+      "text": "Procedure Definitions"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"procedures_defnoreturn\"><field name=\"NAME\">withoutarguments</field><statement name=\"STACK\"><block type=\"text_print\"><value name=\"TEXT\"><shadow type=\"text\"><field name=\"TEXT\">Noargumentreference.</field></shadow></value></block></statement></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"procedures_defnoreturn\"><mutation><arg name=\"fnArgument\"></arg></mutation><field name=\"NAME\">withoneargument</field><statement name=\"STACK\"><block type=\"text_print\"><value name=\"TEXT\"><shadow type=\"text\"><field name=\"TEXT\">Expectedanargumentreferencehere.</field></shadow><block type=\"variables_get\"><field name=\"VAR\">fnArgument</field></block></value></block></statement></block>",
+    }
+  ],
+};
+
+var fieldDefaults = {
+  "kind": "CATEGORY",
+  "name": "Defaults",
+  "contents": [
+    {
+      "kind": "BUTTON",
+      "text": "add blocks to workspace",
+      "callbackkey": "addAllBlocksToWorkspace"
+    },
+    {
+      "kind": "SEP",
+      "gap": "8"
+    },
+    {
+      "kind": "BUTTON",
+      "text": "set random style",
+      "callbackkey": "setRandomStyle"
+    },
+    {
+      "kind": "SEP",
+      "gap": "8"
+    },
+    {
+      "kind": "BUTTON",
+      "text": "toggle enabled",
+      "callbackkey": "toggleEnabled"
+    },
+    {
+      "kind": "SEP",
+      "gap": "8"
+    },
+    {
+      "kind": "BUTTON",
+      "text": "toggle shadow",
+      "callbackkey": "toggleShadow"
+    },
+    {
+      "kind": "SEP",
+      "gap": "8"
+    },
+    {
+      "kind": "BUTTON",
+      "text": "toggle collapsed",
+      "callbackkey": "toggleCollapsed"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_fields_angle\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_fields_checkbox\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_fields_colour\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_fields_colour_options\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_fields_text_input\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_fields_only_text_input\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_fields_multilinetext\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_fields_variable\"></block>",
+    },
+    {
+      "kind": "BUTTON",
+      "text": "randomize label text",
+      "callbackkey": "randomizeLabelText"
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_fields_label_serializable\"></block>",
+    },
+    {
+      "kind": "BUTTON",
+      "text": "change image",
+      "callbackkey": "changeImage"
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_fields_image\"></block>",
+    }
+  ],
+};
+
+var fieldNumbers = {
+  "kind": "CATEGORY",
+  "name": "Numbers",
+  "contents": [
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_numbers_float\"><field name=\"NUM\">123.456</field></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_numbers_hundredths\"><field name=\"NUM\">123.456</field></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_numbers_halves\"><field name=\"NUM\">123.456</field></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_numbers_whole\"><field name=\"NUM\">123.456</field></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_numbers_three_halves\"><field name=\"NUM\">123.456</field></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_numbers_whole_bounded\"><field name=\"NOTE\">60</field></block>",
+    }
+  ],
+};
+
+var fieldAngles = {
+  "kind": "CATEGORY",
+  "name": "Angles",
+  "contents": [
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_angles_clockwise\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_angles_offset\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_angles_wrap\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_angles_round_30\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_angles_round_0\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_angles_protractor\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_angles_compass\"></block>",
+    }
+  ],
+};
+
+var fieldDropDowns = {
+  "kind": "CATEGORY",
+  "name": "Drop-downs",
+  "contents": [
+    {
+      "kind": "LABEL",
+      "text": "Dynamic"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_dropdowns_dynamic\"></block>",
+    },
+    {
+      "kind": "BUTTON",
+      "text": "Add option",
+      "callbackkey": "addDynamicOption"
+    },
+    {
+      "kind": "BUTTON",
+      "text": "Remove option",
+      "callbackkey": "removeDynamicOption"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_dropdowns_dynamic_random\"></block>",
+    },
+    {
+      "kind": "LABEL",
+      "text": "Other"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_dropdowns_long\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_dropdowns_images\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_dropdowns_images_and_text\"></block>",
+    }
+  ],
+};
+
+var fieldImages = {
+  "kind": "CATEGORY",
+  "name": "Images",
+  "contents": [
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_images_datauri\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_images_small\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_images_large\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_images_fliprtl\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_images_missing\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_images_many_icons\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_images_clickhandler\"></block>",
+    }
+  ],
+};
+
+var fieldEmoji = {
+  "kind": "CATEGORY",
+  "name": "Emoji! o((*^ᴗ^*))o",
+  "contents": [
+    {
+      "kind": "LABEL",
+      "text": "Unicode & Emojis"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_style_emoji\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"text\"><field name=\"TEXT\">Robotfaceintextfield:🤖</field></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"text\"><field name=\"TEXT\">Zalgointextfield:B̛̻̦̬̘̰͎̥̈̔͊͞ͅl̡͖̫̺̬̖̣̳̃̀́͑͑̕͟͠͝o̢̹͙̮̫͔͋̉̊̑̿̽̚c̸̹̹̜͙̹̠͋̒͑̊̇͝k̡͉̫͇̖̳͖̊͒́̆̄̎̂̔̕͜͞l̰̙̞̳̩̠͖̯̀̆̈́̿̈̓͗y̨̡̟͇̮͈̬̙̲̏̅̀͘͠</field></block>",
+    }
+  ]
+};
+
+var fieldValidators = {
+  "kind": "CATEGORY",
+  "name": "Validators",
+  "contents": [
+    {
+      "kind": "BUTTON",
+      "text": "add blocks to workspace",
+      "callbackkey": "addAllBlocksToWorkspace"
+    },
+    {
+      "kind": "SEP",
+      "gap": "8"
+    },
+    {
+      "kind": "BUTTON",
+      "text": "set input",
+      "callbackkey": "setInput"
+    },
+    {
+      "kind": "LABEL",
+      "text": "Dispose block"
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_dispose_block\"></block>",
+    },
+    {
+      "kind": "LABEL",
+      "text": "Angles"
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_angle_null\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_angle_mult30_force\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_angle_mult30_null\"></block>",
+    },
+    {
+      "kind": "LABEL",
+      "text": "Checkboxes"
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_checkbox_null\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_checkbox_match\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_checkbox_not_match_null\"></block>",
+    },
+    {
+      "kind": "LABEL",
+      "text": "Colours"
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_colour_null\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_colour_force_red\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_colour_red_null\"></block>",
+    },
+    {
+      "kind": "LABEL",
+      "text": "Dropdowns"
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_dropdown_null\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_dropdown_force_1s\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_dropdown_1s_null\"></block>",
+    },
+    {
+      "kind": "LABEL",
+      "text": "Numbers"
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_number_null\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_number_mult10_force\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_number_mult10_null\"></block>",
+    },
+    {
+      "kind": "LABEL",
+      "text": "Text"
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_text_null\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_text_A\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_text_B\"></block>",
+    },
+    {
+      "kind": "LABEL",
+      "text": "Variables"
+    },
+    {
+      "kind": "SEP",
+      "gap": "8"
+    },
+    {
+      "kind": "BUTTON",
+      "text": "add test variables",
+      "callbackkey": "addVariables",
+      "web-class": "modifiesWorkspace"
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_variable_null\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_variable_force_1s\"></block>",
+    },
+    {
+      "kind": "SEP",
+      "gap": "12"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_validators_variable_1s_null\"></block>",
+    }
+  ],
+};
+
+var mutators = {
+  "kind": "CATEGORY",
+  "name": "Mutators",
+  "contents": [
+    {
+      "kind": "LABEL",
+      "text": "logic_compare"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"logic_compare\"><value name=\"A\"><shadow type=\"math_number\"><field name=\"NUM\">10</field></shadow></value><value name=\"B\"><shadow type=\"math_number\"><field name=\"NUM\">10</field></shadow></value></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"logic_compare\"><value name=\"A\"><block type=\"math_number\"><field name=\"NUM\">10</field></block></value><value name=\"B\"><block type=\"math_number\"><field name=\"NUM\">10</field></block></value></block>",
+    }
+  ],
+};
+
+var style = {
+  "kind": "CATEGORY",
+  "name": "Style",
+  "contents": [
+    {
+      "kind": "LABEL",
+      "text": "Hats"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_style_hat\"></block>",
+    },
+    {
+      "kind": "LABEL",
+      "text": "Colour"
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_style_hex1\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_style_hex2\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_style_hex3\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_style_no_colour\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_style_hex4\"></block>",
+    },
+    {
+      "kind": "BLOCK",
+      "blockxml": "<block type=\"test_style_hex5\"></block>",
+    }
+  ],
+};
+
+/* exported testBlocksToolbox */
+var testBlocksToolbox = [
+  alignCategory,
+  basicCategory,
+  {
+    "kind": "CATEGORY",
+    "name": "Connections",
+    "expanded": "true",
+    "contents": [
+      rowCategory,
+      stackCategory,
+      statementCategory
+    ],
+  },
+  dragCategory,
+  {
+    "kind": "CATEGORY",
+    "name": "Fields",
+    "expanded": "true",
+    "contents": [
+      fieldDefaults,
+      fieldNumbers,
+      fieldAngles,
+      fieldDropDowns,
+      fieldImages,
+      fieldEmoji,
+      fieldValidators
+    ],
+  },
+  mutators,
+  style
+];