diff --git a/core/marker_manager.js b/core/marker_manager.js
index 22090e81e..d8081714f 100644
--- a/core/marker_manager.js
+++ b/core/marker_manager.js
@@ -176,6 +176,8 @@ Blockly.MarkerManager.prototype.dispose = function() {
     this.unregisterMarker(markerId);
   }
   this.markers_ = null;
-  this.cursor_.dispose();
-  this.cursor_ = null;
+  if (this.cursor_) {
+    this.cursor_.dispose();
+    this.cursor_ = null;
+  }
 };
diff --git a/core/workspace_svg.js b/core/workspace_svg.js
index e6d21cb3e..99399691b 100644
--- a/core/workspace_svg.js
+++ b/core/workspace_svg.js
@@ -849,9 +849,9 @@ Blockly.WorkspaceSvg.prototype.dispose = function() {
   if (!this.options.parentWorkspace) {
     // Top-most workspace.  Dispose of the div that the
     // SVG is injected into (i.e. injectionDiv).
-    var div = this.getParentSvg().parentNode;
-    if (div) {
-      Blockly.utils.dom.removeNode(div);
+    var parentSvg = this.getParentSvg();
+    if (parentSvg && parentSvg.parentNode) {
+      Blockly.utils.dom.removeNode(parentSvg.parentNode);
     }
   }
   if (this.resizeHandlerWrapper_) {
diff --git a/tests/mocha/workspace_svg_test.js b/tests/mocha/workspace_svg_test.js
index 5e7487552..ce6d9e900 100644
--- a/tests/mocha/workspace_svg_test.js
+++ b/tests/mocha/workspace_svg_test.js
@@ -32,6 +32,11 @@ suite('WorkspaceSvg', function() {
     delete Blockly.Blocks['test_val_in'];
   });
 
+  test('dispose of WorkspaceSvg without dom throws no error', function() {
+    var ws = new Blockly.WorkspaceSvg(new Blockly.Options({}));
+    ws.dispose();
+  });
+
   test('appendDomToWorkspace alignment', function() {
     var dom = Blockly.Xml.textToDom(
         '<xml xmlns="https://developers.google.com/blockly/xml">' +
@@ -116,6 +121,49 @@ suite('WorkspaceSvg', function() {
     });
   });
 
+  suite('addTopBlock', function() {
+    setup(function() {
+      this.targetWorkspace = new Blockly.Workspace();
+      this.workspace.isFlyout = true;
+      this.workspace.targetWorkspace = this.targetWorkspace;
+      Blockly.defineBlocksWithJsonArray([{
+        "type": "get_var_block",
+        "message0": "%1",
+        "args0": [
+          {
+            "type": "field_variable",
+            "name": "VAR",
+            "variableTypes": ["", "type1", "type2"]
+          }
+        ]
+      }]);
+    });
+
+    teardown(function() {
+      // Have to dispose of the main workspace after the flyout workspace
+      // because it holds the variable map.
+      // Normally the main workspace disposes of the flyout workspace.
+      workspaceTeardown.call(this, this.targetWorkspace);
+      delete Blockly.Blocks['get_var_block'];
+    });
+
+    test('Trivial Flyout is True', function() {
+      this.targetWorkspace.createVariable('name1', '', '1');
+
+      // Flyout.init usually does this binding.
+      this.workspace.variableMap_ = this.targetWorkspace.getVariableMap();
+
+      Blockly.Events.disable();
+      var block = new Blockly.Block(this.workspace, 'get_var_block');
+      block.inputList[0].fieldRow[0].setValue('1');
+      Blockly.Events.enable();
+
+      this.workspace.removeTopBlock(block);
+      this.workspace.addTopBlock(block);
+      assertVariableValues(this.workspace, 'name1', '', '1');
+    });
+  });
+
   suite('Workspace Base class', function() {
     testAWorkspace();
   });
diff --git a/tests/mocha/workspace_test.js b/tests/mocha/workspace_test.js
index a92f45072..0c3d47907 100644
--- a/tests/mocha/workspace_test.js
+++ b/tests/mocha/workspace_test.js
@@ -245,34 +245,6 @@ function testAWorkspace() {
     });
   });
 
-  suite('addTopBlock', function() {
-    setup(function() {
-      this.targetWorkspace = new Blockly.Workspace();
-      this.workspace.isFlyout = true;
-      this.workspace.targetWorkspace = this.targetWorkspace;
-    });
-
-    teardown(function() {
-      // Have to dispose of the main workspace after the flyout workspace
-      // because it holds the variable map.
-      // Normally the main workspace disposes of the flyout workspace.
-      workspaceTeardown.call(this, this.targetWorkspace);
-    });
-
-    test('Trivial Flyout is True', function() {
-      this.targetWorkspace.createVariable('name1', '', '1');
-
-      // Flyout.init usually does this binding.
-      this.workspace.variableMap_ = this.targetWorkspace.getVariableMap();
-
-      var block = createVarBlocksNoEvents(this.workspace, ['1'])[0];
-
-      this.workspace.removeTopBlock(block);
-      this.workspace.addTopBlock(block);
-      assertVariableValues(this.workspace, 'name1', '', '1');
-    });
-  });
-
   suite('getTopBlocks(ordered=true)', function() {
     test('Empty workspace', function() {
       chai.assert.equal(this.workspace.getTopBlocks(true).length, 0);
@@ -595,11 +567,13 @@ function testAWorkspace() {
 
   suite('getById', function() {
     setup(function() {
-      this.workspaceB = new Blockly.Workspace();
+      this.workspaceB = this.workspace.rendered ?
+          new Blockly.WorkspaceSvg(new Blockly.Options({})) :
+          new Blockly.Workspace();
     });
 
     teardown(function() {
-      this.workspaceB.dispose();
+      workspaceTeardown.call(this, this.workspaceB);
     });
 
     test('Trivial', function() {
@@ -627,11 +601,13 @@ function testAWorkspace() {
     setup(function() {
       this.blockA = this.workspace.newBlock('');
       this.blockB = this.workspace.newBlock('');
-      this.workspaceB = new Blockly.Workspace();
+      this.workspaceB = this.workspace.rendered ?
+          new Blockly.WorkspaceSvg(new Blockly.Options({})) :
+          new Blockly.Workspace();
     });
 
     teardown(function() {
-      this.workspaceB.dispose();
+      workspaceTeardown.call(this, this.workspaceB);
     });
 
     test('Trivial', function() {