diff --git a/core/block.ts b/core/block.ts
index 8f64b20a2..53a1063d8 100644
--- a/core/block.ts
+++ b/core/block.ts
@@ -202,7 +202,8 @@ export class Block implements IASTNodeLocation, IDeletable {
   /** Name of the type of hat. */
   hat?: string;
 
-  rendered: boolean | null = null;
+  /** Is this block a BlockSVG? */
+  readonly rendered: boolean = false;
 
   /**
    * String for block help, or function that returns a URL. Null for no help.
diff --git a/core/block_svg.ts b/core/block_svg.ts
index f8ac57684..17e6aa3a4 100644
--- a/core/block_svg.ts
+++ b/core/block_svg.ts
@@ -117,7 +117,10 @@ export class BlockSvg
   style: BlockStyle;
   /** @internal */
   pathObject: IPathObject;
-  override rendered = false;
+
+  /** Is this block a BlockSVG? */
+  override readonly rendered = true;
+
   private visuallyDisabled = false;
 
   /**
@@ -650,12 +653,6 @@ export class BlockSvg
    * @internal
    */
   updateComponentLocations(blockOrigin: Coordinate) {
-    if (!this.rendered) {
-      // Rendering is required to lay out the blocks.
-      // This is probably an invisible block attached to a collapsed block.
-      return;
-    }
-
     if (!this.dragging) this.updateConnectionLocations(blockOrigin);
     this.updateIconLocations(blockOrigin);
     this.updateFieldLocations(blockOrigin);
@@ -789,7 +786,7 @@ export class BlockSvg
     Tooltip.dispose();
     ContextMenu.hide();
 
-    if (animate && this.rendered) {
+    if (animate) {
       this.unplug(healStack);
       blockAnimations.disposeUiEffect(this);
     }
@@ -806,8 +803,6 @@ export class BlockSvg
     if (this.isDeadOrDying()) return;
     super.disposeInternal();
 
-    this.rendered = false;
-
     if (common.getSelected() === this) {
       this.unselect();
       this.workspace.cancelCurrentGesture();
@@ -991,13 +986,11 @@ export class BlockSvg
 
     if (icon instanceof MutatorIcon) this.mutator = icon;
 
-    if (this.rendered) {
-      icon.initView(this.createIconPointerDownListener(icon));
-      icon.applyColour();
-      icon.updateEditable();
-      this.queueRender();
-      this.bumpNeighbours();
-    }
+    icon.initView(this.createIconPointerDownListener(icon));
+    icon.applyColour();
+    icon.updateEditable();
+    this.queueRender();
+    this.bumpNeighbours();
 
     return icon;
   }
@@ -1021,10 +1014,9 @@ export class BlockSvg
 
     if (type.equals(MutatorIcon.TYPE)) this.mutator = null;
 
-    if (this.rendered) {
-      this.queueRender();
-      this.bumpNeighbours();
-    }
+    this.queueRender();
+    this.bumpNeighbours();
+
     return removed;
   }
 
@@ -1036,7 +1028,7 @@ export class BlockSvg
   override setEnabled(enabled: boolean) {
     if (this.isEnabled() !== enabled) {
       super.setEnabled(enabled);
-      if (this.rendered && !this.getInheritedDisabled()) {
+      if (!this.getInheritedDisabled()) {
         this.updateDisabled();
       }
     }
@@ -1049,9 +1041,6 @@ export class BlockSvg
    * @param highlighted True if highlighted.
    */
   setHighlighted(highlighted: boolean) {
-    if (!this.rendered) {
-      return;
-    }
     this.pathObject.updateHighlighted(highlighted);
   }
 
@@ -1183,11 +1172,8 @@ export class BlockSvg
     opt_check?: string | string[] | null,
   ) {
     super.setPreviousStatement(newBoolean, opt_check);
-
-    if (this.rendered) {
-      this.queueRender();
-      this.bumpNeighbours();
-    }
+    this.queueRender();
+    this.bumpNeighbours();
   }
 
   /**
@@ -1202,11 +1188,8 @@ export class BlockSvg
     opt_check?: string | string[] | null,
   ) {
     super.setNextStatement(newBoolean, opt_check);
-
-    if (this.rendered) {
-      this.queueRender();
-      this.bumpNeighbours();
-    }
+    this.queueRender();
+    this.bumpNeighbours();
   }
 
   /**
@@ -1221,11 +1204,8 @@ export class BlockSvg
     opt_check?: string | string[] | null,
   ) {
     super.setOutput(newBoolean, opt_check);
-
-    if (this.rendered) {
-      this.queueRender();
-      this.bumpNeighbours();
-    }
+    this.queueRender();
+    this.bumpNeighbours();
   }
 
   /**
@@ -1235,11 +1215,8 @@ export class BlockSvg
    */
   override setInputsInline(newBoolean: boolean) {
     super.setInputsInline(newBoolean);
-
-    if (this.rendered) {
-      this.queueRender();
-      this.bumpNeighbours();
-    }
+    this.queueRender();
+    this.bumpNeighbours();
   }
 
   /**
@@ -1253,13 +1230,8 @@ export class BlockSvg
    */
   override removeInput(name: string, opt_quiet?: boolean): boolean {
     const removed = super.removeInput(name, opt_quiet);
-
-    if (this.rendered) {
-      this.queueRender();
-      // Removing an input will cause the block to change shape.
-      this.bumpNeighbours();
-    }
-
+    this.queueRender();
+    this.bumpNeighbours();
     return removed;
   }
 
@@ -1271,23 +1243,15 @@ export class BlockSvg
    */
   override moveNumberedInputBefore(inputIndex: number, refIndex: number) {
     super.moveNumberedInputBefore(inputIndex, refIndex);
-
-    if (this.rendered) {
-      this.queueRender();
-      // Moving an input will cause the block to change shape.
-      this.bumpNeighbours();
-    }
+    this.queueRender();
+    this.bumpNeighbours();
   }
 
   /** @override */
   override appendInput(input: Input): Input {
     super.appendInput(input);
-
-    if (this.rendered) {
-      this.queueRender();
-      // Adding an input will cause the block to change shape.
-      this.bumpNeighbours();
-    }
+    this.queueRender();
+    this.bumpNeighbours();
     return input;
   }
 
@@ -1341,28 +1305,25 @@ export class BlockSvg
    * Returns connections originating from this block.
    *
    * @param all If true, return all connections even hidden ones.
-   *     Otherwise, for a non-rendered block return an empty list, and for a
-   *     collapsed block don't return inputs connections.
+   *     Otherwise, for a collapsed block don't return inputs connections.
    * @returns Array of connections.
    * @internal
    */
   override getConnections_(all: boolean): RenderedConnection[] {
     const myConnections = [];
-    if (all || this.rendered) {
-      if (this.outputConnection) {
-        myConnections.push(this.outputConnection);
-      }
-      if (this.previousConnection) {
-        myConnections.push(this.previousConnection);
-      }
-      if (this.nextConnection) {
-        myConnections.push(this.nextConnection);
-      }
-      if (all || !this.collapsed_) {
-        for (let i = 0, input; (input = this.inputList[i]); i++) {
-          if (input.connection) {
-            myConnections.push(input.connection as RenderedConnection);
-          }
+    if (this.outputConnection) {
+      myConnections.push(this.outputConnection);
+    }
+    if (this.previousConnection) {
+      myConnections.push(this.previousConnection);
+    }
+    if (this.nextConnection) {
+      myConnections.push(this.nextConnection);
+    }
+    if (all || !this.collapsed_) {
+      for (let i = 0, input; (input = this.inputList[i]); i++) {
+        if (input.connection) {
+          myConnections.push(input.connection as RenderedConnection);
         }
       }
     }
@@ -1573,7 +1534,6 @@ export class BlockSvg
    * @internal
    */
   renderEfficiently() {
-    this.rendered = true;
     dom.startTextWidthCache();
 
     if (this.isCollapsed()) {
diff --git a/core/inputs/input.ts b/core/inputs/input.ts
index 96498ec1b..a94102aca 100644
--- a/core/inputs/input.ts
+++ b/core/inputs/input.ts
@@ -124,7 +124,6 @@ export class Input {
 
     if (this.sourceBlock.rendered) {
       (this.sourceBlock as BlockSvg).queueRender();
-      // Adding a field will cause the block to change shape.
       this.sourceBlock.bumpNeighbours();
     }
     return index;
@@ -146,7 +145,6 @@ export class Input {
         this.fieldRow.splice(i, 1);
         if (this.sourceBlock.rendered) {
           (this.sourceBlock as BlockSvg).queueRender();
-          // Removing a field will cause the block to change shape.
           this.sourceBlock.bumpNeighbours();
         }
         return true;
@@ -274,7 +272,7 @@ export class Input {
 
   /** Initialize the fields on this input. */
   init() {
-    if (!this.sourceBlock.workspace.rendered) {
+    if (!this.sourceBlock.rendered) {
       return; // Headless blocks don't need fields initialized.
     }
     for (let i = 0; i < this.fieldRow.length; i++) {
diff --git a/core/insertion_marker_manager.ts b/core/insertion_marker_manager.ts
index cc507bd70..302dd47c6 100644
--- a/core/insertion_marker_manager.ts
+++ b/core/insertion_marker_manager.ts
@@ -176,18 +176,16 @@ export class InsertionMarkerManager {
     eventUtils.enable();
     const {local, closest} = this.activeCandidate;
     local.connect(closest);
-    if (this.topBlock.rendered) {
-      const inferiorConnection = local.isSuperior() ? closest : local;
-      const rootBlock = this.topBlock.getRootBlock();
+    const inferiorConnection = local.isSuperior() ? closest : local;
+    const rootBlock = this.topBlock.getRootBlock();
 
-      finishQueuedRenders().then(() => {
-        blockAnimations.connectionUiEffect(inferiorConnection.getSourceBlock());
-        // bringToFront is incredibly expensive. Delay until the next frame.
-        setTimeout(() => {
-          rootBlock.bringToFront();
-        }, 0);
-      });
-    }
+    finishQueuedRenders().then(() => {
+      blockAnimations.connectionUiEffect(inferiorConnection.getSourceBlock());
+      // bringToFront is incredibly expensive. Delay until the next frame.
+      setTimeout(() => {
+        rootBlock.bringToFront();
+      }, 0);
+    });
   }
 
   /**
diff --git a/core/rendered_connection.ts b/core/rendered_connection.ts
index 08c0471a2..e68450883 100644
--- a/core/rendered_connection.ts
+++ b/core/rendered_connection.ts
@@ -502,16 +502,12 @@ export class RenderedConnection extends Connection {
     const parent = parentConnection.getSourceBlock() as BlockSvg;
     const child = childConnection.getSourceBlock() as BlockSvg;
     super.disconnectInternal(setParent);
-    // Rerender the parent so that it may reflow.
-    if (parent.rendered) {
-      parent.queueRender();
-    }
-    if (child.rendered) {
-      child.updateDisabled();
-      child.queueRender();
-      // Reset visibility, since the child is now a top block.
-      child.getSvgRoot().style.display = 'block';
-    }
+
+    parent.queueRender();
+    child.updateDisabled();
+    child.queueRender();
+    // Reset visibility, since the child is now a top block.
+    child.getSvgRoot().style.display = 'block';
   }
 
   /**
@@ -554,29 +550,10 @@ export class RenderedConnection extends Connection {
 
     const parentBlock = this.getSourceBlock();
     const childBlock = renderedChildConnection.getSourceBlock();
-    const parentRendered = parentBlock.rendered;
-    const childRendered = childBlock.rendered;
 
-    if (parentRendered) {
-      parentBlock.updateDisabled();
-    }
-    if (childRendered) {
-      childBlock.updateDisabled();
-    }
-    if (parentRendered && childRendered) {
-      if (
-        this.type === ConnectionType.NEXT_STATEMENT ||
-        this.type === ConnectionType.PREVIOUS_STATEMENT
-      ) {
-        // Child block may need to square off its corners if it is in a stack.
-        // Rendering a child will render its parent.
-        childBlock.queueRender();
-      } else {
-        // Child block does not change shape.  Rendering the parent node will
-        // move its connected children into position.
-        parentBlock.queueRender();
-      }
-    }
+    parentBlock.updateDisabled();
+    childBlock.updateDisabled();
+    childBlock.queueRender();
 
     // The input the child block is connected to (if any).
     const parentInput = parentBlock.getInputWithBlock(childBlock);
@@ -617,9 +594,7 @@ export class RenderedConnection extends Connection {
    */
   override setCheck(check: string | string[] | null): RenderedConnection {
     super.setCheck(check);
-    if (this.sourceBlock_.rendered) {
-      this.sourceBlock_.queueRender();
-    }
+    this.sourceBlock_.queueRender();
     return this;
   }
 }
diff --git a/tests/mocha/icon_test.js b/tests/mocha/icon_test.js
index 4ff27997f..63c723495 100644
--- a/tests/mocha/icon_test.js
+++ b/tests/mocha/icon_test.js
@@ -68,24 +68,6 @@ suite('Icon', function () {
         );
       });
 
-      test('initView is called by headful blocks during initSvg', function () {
-        const workspace = createWorkspaceSvg();
-        const block = createUninitializedBlock(workspace);
-        const icon = new MockIcon();
-        const initViewSpy = sinon.spy(icon, 'initView');
-
-        block.addIcon(icon);
-        chai.assert.isFalse(
-          initViewSpy.called,
-          'Expected initView to not be called before initing svg',
-        );
-        block.initSvg();
-        chai.assert.isTrue(
-          initViewSpy.calledOnce,
-          'Expected initView to be called',
-        );
-      });
-
       test(
         'initView is called by headful blocks that are currently ' +
           'rendered when the icon is added',
@@ -120,24 +102,6 @@ suite('Icon', function () {
         );
       });
 
-      test('applyColour is called by headful blocks during initSvg', function () {
-        const workspace = createWorkspaceSvg();
-        const block = createUninitializedBlock(workspace);
-        const icon = new MockIcon();
-        const applyColourSpy = sinon.spy(icon, 'applyColour');
-
-        block.addIcon(icon);
-        chai.assert.isFalse(
-          applyColourSpy.called,
-          'Expected applyCOlour to not be called before initing svg',
-        );
-        block.initSvg();
-        chai.assert.isTrue(
-          applyColourSpy.calledOnce,
-          'Expected applyColour to be called',
-        );
-      });
-
       test(
         'applyColour is called by headful blocks that are currently ' +
           'rendered when the icon is added',
@@ -231,24 +195,6 @@ suite('Icon', function () {
         );
       });
 
-      test('updateEditable is called by headful blocks during initSvg', function () {
-        const workspace = createWorkspaceSvg();
-        const block = createUninitializedBlock(workspace);
-        const icon = new MockIcon();
-        const updateEditableSpy = sinon.spy(icon, 'updateEditable');
-
-        block.addIcon(icon);
-        chai.assert.isFalse(
-          updateEditableSpy.called,
-          'Expected updateEditable to not be called before initing svg',
-        );
-        block.initSvg();
-        chai.assert.isTrue(
-          updateEditableSpy.calledOnce,
-          'Expected updateEditable to be called',
-        );
-      });
-
       test(
         'updateEditable is called by headful blocks that are currently ' +
           'rendered when the icon is added',
diff --git a/tests/mocha/test_helpers/workspace.js b/tests/mocha/test_helpers/workspace.js
index 7654feba2..6da113f8b 100644
--- a/tests/mocha/test_helpers/workspace.js
+++ b/tests/mocha/test_helpers/workspace.js
@@ -781,7 +781,9 @@ export function testAWorkspace() {
         const xml = Blockly.utils.xml.textToDom(xmlText);
         Blockly.Xml.domToBlock(xml, this.workspace);
         this.workspace.getTopBlocks()[0].dispose(false);
+        this.clock.runAll();
         this.workspace.undo();
+        this.clock.runAll();
         const newXml = Blockly.Xml.workspaceToDom(this.workspace);
         assertNodesEqual(newXml.firstChild, xml);
       }
@@ -909,11 +911,14 @@ export function testAWorkspace() {
       function testUndoConnect(xmlText, parentId, childId, func) {
         const xml = Blockly.utils.xml.textToDom(xmlText);
         Blockly.Xml.domToWorkspace(xml, this.workspace);
+        this.clock.runAll();
 
         const parent = this.workspace.getBlockById(parentId);
         const child = this.workspace.getBlockById(childId);
         func.call(this, parent, child);
+        this.clock.runAll();
         this.workspace.undo();
+        this.clock.runAll();
 
         const newXml = Blockly.Xml.workspaceToDom(this.workspace);
         assertNodesEqual(newXml, xml);
@@ -922,8 +927,8 @@ export function testAWorkspace() {
       test('Stack', function () {
         const xml =
           '<xml>' +
-          '  <block type="stack_block" id="1"></block>' +
-          '  <block type="stack_block" id="2"></block>' +
+          '  <block type="stack_block" id="1" x="10" y="10"></block>' +
+          '  <block type="stack_block" id="2" x="50" y="50"></block>' +
           '</xml>';
 
         testUndoConnect.call(this, xml, '1', '2', (parent, child) => {
@@ -934,8 +939,8 @@ export function testAWorkspace() {
       test('Row', function () {
         const xml =
           '<xml>' +
-          '  <block type="row_block" id="1"></block>' +
-          '  <block type="row_block" id="2"></block>' +
+          '  <block type="row_block" id="1" x="10" y="10"></block>' +
+          '  <block type="row_block" id="2" x="50" y="50"></block>' +
           '</xml>';
 
         testUndoConnect.call(this, xml, '1', '2', (parent, child) => {
@@ -946,8 +951,8 @@ export function testAWorkspace() {
       test('Statement', function () {
         const xml =
           '<xml>' +
-          '  <block type="statement_block" id="1"></block>' +
-          '  <block type="stack_block" id="2"></block>' +
+          '  <block type="statement_block" id="1" x="10" y="10"></block>' +
+          '  <block type="stack_block" id="2" x="50" y="50"></block>' +
           '</xml>';
 
         testUndoConnect.call(this, xml, '1', '2', (parent, child) => {
@@ -960,12 +965,12 @@ export function testAWorkspace() {
       test('Stack w/ child', function () {
         const xml =
           '<xml>' +
-          '  <block type="stack_block" id="1">' +
+          '  <block type="stack_block" id="1" x="10" y="10">' +
           '    <next>' +
           '      <block type="stack_block" id="3"></block>' +
           '    </next>' +
           '  </block>' +
-          '  <block type="stack_block" id="2"></block>' +
+          '  <block type="stack_block" id="2" x="50" y="50"></block>' +
           '</xml>';
 
         testUndoConnect.call(this, xml, '1', '2', (parent, child) => {
@@ -976,12 +981,12 @@ export function testAWorkspace() {
       test('Row w/ child', function () {
         const xml =
           '<xml>' +
-          '  <block type="row_block" id="1">' +
+          '  <block type="row_block" id="1" x="10" y="10">' +
           '    <value name="INPUT">' +
           '      <block type="row_block" id="3"></block>' +
           '    </value>' +
           '  </block>' +
-          '  <block type="row_block" id="2"></block>' +
+          '  <block type="row_block" id="2" x="50" y="50"></block>' +
           '</xml>';
 
         testUndoConnect.call(this, xml, '1', '2', (parent, child) => {
@@ -992,12 +997,12 @@ export function testAWorkspace() {
       test('Statement w/ child', function () {
         const xml =
           '<xml>' +
-          '  <block type="statement_block" id="1">' +
+          '  <block type="statement_block" id="1" x="10" y="10">' +
           '    <statement name="STATEMENT">' +
           '      <block type="stack_block" id="3"></block>' +
           '    </statement>' +
           '  </block>' +
-          '  <block type="stack_block" id="2"></block>' +
+          '  <block type="stack_block" id="2" x="100" y="100"></block>' +
           '</xml>';
 
         testUndoConnect.call(this, xml, '1', '2', (parent, child) => {
@@ -1010,12 +1015,12 @@ export function testAWorkspace() {
       test('Stack w/ shadow', function () {
         const xml =
           '<xml>' +
-          '  <block type="stack_block" id="1">' +
+          '  <block type="stack_block" id="1" x="10" y="10">' +
           '    <next>' +
           '      <shadow type="stack_block" id="3"></shadow>' +
           '    </next>' +
           '  </block>' +
-          '  <block type="stack_block" id="2"></block>' +
+          '  <block type="stack_block" id="2" x="50" y="50"></block>' +
           '</xml>';
 
         testUndoConnect.call(this, xml, '1', '2', (parent, child) => {
@@ -1026,12 +1031,12 @@ export function testAWorkspace() {
       test('Row w/ shadow', function () {
         const xml =
           '<xml>' +
-          '  <block type="row_block" id="1">' +
+          '  <block type="row_block" id="1" x="10" y="10">' +
           '    <value name="INPUT">' +
           '      <shadow type="row_block" id="3"></shadow>' +
           '    </value>' +
           '  </block>' +
-          '  <block type="row_block" id="2"></block>' +
+          '  <block type="row_block" id="2" x="50" y="50"></block>' +
           '</xml>';
 
         testUndoConnect.call(this, xml, '1', '2', (parent, child) => {
@@ -1042,12 +1047,12 @@ export function testAWorkspace() {
       test('Statement w/ shadow', function () {
         const xml =
           '<xml>' +
-          '  <block type="statement_block" id="1">' +
+          '  <block type="statement_block" id="1" x="10" y="10">' +
           '    <statement name="STATEMENT">' +
           '      <shadow type="stack_block" id="3"></shadow>' +
           '    </statement>' +
           '  </block>' +
-          '  <block type="stack_block" id="2"></block>' +
+          '  <block type="stack_block" id="2" x="100" y="100"></block>' +
           '</xml>';
 
         testUndoConnect.call(this, xml, '1', '2', (parent, child) => {
@@ -1102,6 +1107,7 @@ export function testAWorkspace() {
       function testUndoDisconnect(xmlText, childId) {
         const xml = Blockly.utils.xml.textToDom(xmlText);
         Blockly.Xml.domToWorkspace(xml, this.workspace);
+        this.clock.runAll();
 
         const child = this.workspace.getBlockById(childId);
         if (child.outputConnection) {
@@ -1109,7 +1115,9 @@ export function testAWorkspace() {
         } else {
           child.previousConnection.disconnect();
         }
+        this.clock.runAll();
         this.workspace.undo();
+        this.clock.runAll();
 
         const newXml = Blockly.Xml.workspaceToDom(this.workspace);
         assertNodesEqual(newXml, xml);
@@ -1262,8 +1270,10 @@ export function testAWorkspace() {
       suite('createVariable', function () {
         test('Undo only', function () {
           createTwoVarsDifferentTypes(this.workspace);
+          this.clock.runAll();
 
           this.workspace.undo();
+          this.clock.runAll();
           assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
           chai.assert.isNull(this.workspace.getVariableById('id2'));
 
@@ -1274,8 +1284,10 @@ export function testAWorkspace() {
 
         test('Undo and redo', function () {
           createTwoVarsDifferentTypes(this.workspace);
+          this.clock.runAll();
 
           this.workspace.undo();
+          this.clock.runAll();
           assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
           chai.assert.isNull(this.workspace.getVariableById('id2'));
 
@@ -1300,14 +1312,18 @@ export function testAWorkspace() {
       suite('deleteVariableById', function () {
         test('Undo only no usages', function () {
           createTwoVarsDifferentTypes(this.workspace);
+          this.clock.runAll();
           this.workspace.deleteVariableById('id1');
           this.workspace.deleteVariableById('id2');
+          this.clock.runAll();
 
           this.workspace.undo();
+          this.clock.runAll();
           chai.assert.isNull(this.workspace.getVariableById('id1'));
           assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
 
           this.workspace.undo();
+          this.clock.runAll();
           assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
           assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
         });
@@ -1316,15 +1332,19 @@ export function testAWorkspace() {
           createTwoVarsDifferentTypes(this.workspace);
           // Create blocks to refer to both of them.
           createVarBlocksNoEvents(this.workspace, ['id1', 'id2']);
+          this.clock.runAll();
           this.workspace.deleteVariableById('id1');
           this.workspace.deleteVariableById('id2');
+          this.clock.runAll();
 
           this.workspace.undo();
+          this.clock.runAll();
           assertBlockVarModelName(this.workspace, 0, 'name2');
           chai.assert.isNull(this.workspace.getVariableById('id1'));
           assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
 
           this.workspace.undo();
+          this.clock.runAll();
           assertBlockVarModelName(this.workspace, 0, 'name2');
           assertBlockVarModelName(this.workspace, 1, 'name1');
           assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
@@ -1333,24 +1353,31 @@ export function testAWorkspace() {
 
         test('Reference exists no usages', function () {
           createTwoVarsDifferentTypes(this.workspace);
+          this.clock.runAll();
           this.workspace.deleteVariableById('id1');
           this.workspace.deleteVariableById('id2');
+          this.clock.runAll();
 
           this.workspace.undo();
+          this.clock.runAll();
           chai.assert.isNull(this.workspace.getVariableById('id1'));
           assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
 
           this.workspace.undo(true);
+          this.clock.runAll();
           // Expect that both variables are deleted
           chai.assert.isNull(this.workspace.getVariableById('id1'));
           chai.assert.isNull(this.workspace.getVariableById('id2'));
 
           this.workspace.undo();
+          this.clock.runAll();
           this.workspace.undo();
+          this.clock.runAll();
           assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
           assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
 
           this.workspace.undo(true);
+          this.clock.runAll();
           // Expect that variable 'id2' is recreated
           chai.assert.isNull(this.workspace.getVariableById('id1'));
           assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
@@ -1360,28 +1387,35 @@ export function testAWorkspace() {
           createTwoVarsDifferentTypes(this.workspace);
           // Create blocks to refer to both of them.
           createVarBlocksNoEvents(this.workspace, ['id1', 'id2']);
+          this.clock.runAll();
           this.workspace.deleteVariableById('id1');
           this.workspace.deleteVariableById('id2');
+          this.clock.runAll();
 
           this.workspace.undo();
+          this.clock.runAll();
           assertBlockVarModelName(this.workspace, 0, 'name2');
           chai.assert.isNull(this.workspace.getVariableById('id1'));
           assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
 
           this.workspace.undo(true);
+          this.clock.runAll();
           // Expect that both variables are deleted
           chai.assert.equal(this.workspace.getTopBlocks(false).length, 0);
           chai.assert.isNull(this.workspace.getVariableById('id1'));
           chai.assert.isNull(this.workspace.getVariableById('id2'));
 
           this.workspace.undo();
+          this.clock.runAll();
           this.workspace.undo();
+          this.clock.runAll();
           assertBlockVarModelName(this.workspace, 0, 'name2');
           assertBlockVarModelName(this.workspace, 1, 'name1');
           assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
           assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
 
           this.workspace.undo(true);
+          this.clock.runAll();
           // Expect that variable 'id2' is recreated
           assertBlockVarModelName(this.workspace, 0, 'name2');
           chai.assert.isNull(this.workspace.getVariableById('id1'));
@@ -1391,6 +1425,7 @@ export function testAWorkspace() {
         test('Delete same variable twice no usages', function () {
           this.workspace.createVariable('name1', 'type1', 'id1');
           this.workspace.deleteVariableById('id1');
+          this.clock.runAll();
           const workspace = this.workspace;
           assertWarnings(() => {
             workspace.deleteVariableById('id1');
@@ -1406,21 +1441,26 @@ export function testAWorkspace() {
 
           // Undo delete
           this.workspace.undo();
+          this.clock.runAll();
           assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
 
           // Redo delete
           this.workspace.undo(true);
+          this.clock.runAll();
           chai.assert.isNull(this.workspace.getVariableById('id1'));
 
           // Redo delete, nothing should happen
           this.workspace.undo(true);
+          this.clock.runAll();
           chai.assert.isNull(this.workspace.getVariableById('id1'));
         });
 
         test('Delete same variable twice with usages', function () {
           this.workspace.createVariable('name1', 'type1', 'id1');
           createVarBlocksNoEvents(this.workspace, ['id1']);
+          this.clock.runAll();
           this.workspace.deleteVariableById('id1');
+          this.clock.runAll();
           const workspace = this.workspace;
           assertWarnings(() => {
             workspace.deleteVariableById('id1');
@@ -1437,16 +1477,19 @@ export function testAWorkspace() {
 
           // Undo delete
           this.workspace.undo();
+          this.clock.runAll();
           assertBlockVarModelName(this.workspace, 0, 'name1');
           assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
 
           // Redo delete
           this.workspace.undo(true);
+          this.clock.runAll();
           chai.assert.equal(this.workspace.getTopBlocks(false).length, 0);
           chai.assert.isNull(this.workspace.getVariableById('id1'));
 
           // Redo delete, nothing should happen
           this.workspace.undo(true);
+          this.clock.runAll();
           chai.assert.equal(this.workspace.getTopBlocks(false).length, 0);
           chai.assert.isNull(this.workspace.getVariableById('id1'));
         });
@@ -1459,46 +1502,58 @@ export function testAWorkspace() {
 
         test('Reference exists no usages rename to name2', function () {
           this.workspace.renameVariableById('id1', 'name2');
+          this.clock.runAll();
 
           this.workspace.undo();
+          this.clock.runAll();
           assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
 
           this.workspace.undo(true);
+          this.clock.runAll();
           assertVariableValues(this.workspace, 'name2', 'type1', 'id1');
         });
 
         test('Reference exists with usages rename to name2', function () {
           createVarBlocksNoEvents(this.workspace, ['id1']);
           this.workspace.renameVariableById('id1', 'name2');
+          this.clock.runAll();
 
           this.workspace.undo();
+          this.clock.runAll();
           assertBlockVarModelName(this.workspace, 0, 'name1');
           assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
 
           this.workspace.undo(true);
+          this.clock.runAll();
           assertBlockVarModelName(this.workspace, 0, 'name2');
           assertVariableValues(this.workspace, 'name2', 'type1', 'id1');
         });
 
         test('Reference exists different capitalization no usages rename to Name1', function () {
           this.workspace.renameVariableById('id1', 'Name1');
+          this.clock.runAll();
 
           this.workspace.undo();
+          this.clock.runAll();
           assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
 
           this.workspace.undo(true);
+          this.clock.runAll();
           assertVariableValues(this.workspace, 'Name1', 'type1', 'id1');
         });
 
         test('Reference exists different capitalization with usages rename to Name1', function () {
           createVarBlocksNoEvents(this.workspace, ['id1']);
           this.workspace.renameVariableById('id1', 'Name1');
+          this.clock.runAll();
 
           this.workspace.undo();
+          this.clock.runAll();
           assertBlockVarModelName(this.workspace, 0, 'name1');
           assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
 
           this.workspace.undo(true);
+          this.clock.runAll();
           assertBlockVarModelName(this.workspace, 0, 'Name1');
           assertVariableValues(this.workspace, 'Name1', 'type1', 'id1');
         });
@@ -1507,12 +1562,15 @@ export function testAWorkspace() {
           test('Same type no usages rename variable with id1 to name2', function () {
             this.workspace.createVariable('name2', 'type1', 'id2');
             this.workspace.renameVariableById('id1', 'name2');
+            this.clock.runAll();
 
             this.workspace.undo();
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
             assertVariableValues(this.workspace, 'name2', 'type1', 'id2');
 
             this.workspace.undo(true);
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'name2', 'type1', 'id2');
             chai.assert.isNull(this.workspace.getVariableById('id1'));
           });
@@ -1521,14 +1579,17 @@ export function testAWorkspace() {
             this.workspace.createVariable('name2', 'type1', 'id2');
             createVarBlocksNoEvents(this.workspace, ['id1', 'id2']);
             this.workspace.renameVariableById('id1', 'name2');
+            this.clock.runAll();
 
             this.workspace.undo();
+            this.clock.runAll();
             assertBlockVarModelName(this.workspace, 0, 'name1');
             assertBlockVarModelName(this.workspace, 1, 'name2');
             assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
             assertVariableValues(this.workspace, 'name2', 'type1', 'id2');
 
             this.workspace.undo(true);
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'name2', 'type1', 'id2');
             chai.assert.isNull(this.workspace.getVariableById('id1'));
           });
@@ -1536,12 +1597,15 @@ export function testAWorkspace() {
           test('Same type different capitalization no usages rename variable with id1 to Name2', function () {
             this.workspace.createVariable('name2', 'type1', 'id2');
             this.workspace.renameVariableById('id1', 'Name2');
+            this.clock.runAll();
 
             this.workspace.undo();
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
             assertVariableValues(this.workspace, 'name2', 'type1', 'id2');
 
             this.workspace.undo(true);
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'Name2', 'type1', 'id2');
             chai.assert.isNull(this.workspace.getVariable('name1'));
           });
@@ -1550,14 +1614,17 @@ export function testAWorkspace() {
             this.workspace.createVariable('name2', 'type1', 'id2');
             createVarBlocksNoEvents(this.workspace, ['id1', 'id2']);
             this.workspace.renameVariableById('id1', 'Name2');
+            this.clock.runAll();
 
             this.workspace.undo();
+            this.clock.runAll();
             assertBlockVarModelName(this.workspace, 0, 'name1');
             assertBlockVarModelName(this.workspace, 1, 'name2');
             assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
             assertVariableValues(this.workspace, 'name2', 'type1', 'id2');
 
             this.workspace.undo(true);
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'Name2', 'type1', 'id2');
             chai.assert.isNull(this.workspace.getVariableById('id1'));
             assertBlockVarModelName(this.workspace, 0, 'Name2');
@@ -1567,12 +1634,15 @@ export function testAWorkspace() {
           test('Different type no usages rename variable with id1 to name2', function () {
             this.workspace.createVariable('name2', 'type2', 'id2');
             this.workspace.renameVariableById('id1', 'name2');
+            this.clock.runAll();
 
             this.workspace.undo();
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
             assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
 
             this.workspace.undo(true);
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'name2', 'type1', 'id1');
             assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
           });
@@ -1581,14 +1651,17 @@ export function testAWorkspace() {
             this.workspace.createVariable('name2', 'type2', 'id2');
             createVarBlocksNoEvents(this.workspace, ['id1', 'id2']);
             this.workspace.renameVariableById('id1', 'name2');
+            this.clock.runAll();
 
             this.workspace.undo();
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
             assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
             assertBlockVarModelName(this.workspace, 0, 'name1');
             assertBlockVarModelName(this.workspace, 1, 'name2');
 
             this.workspace.undo(true);
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'name2', 'type1', 'id1');
             assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
             assertBlockVarModelName(this.workspace, 0, 'name2');
@@ -1598,12 +1671,15 @@ export function testAWorkspace() {
           test('Different type different capitalization no usages rename variable with id1 to Name2', function () {
             this.workspace.createVariable('name2', 'type2', 'id2');
             this.workspace.renameVariableById('id1', 'Name2');
+            this.clock.runAll();
 
             this.workspace.undo();
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
             assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
 
             this.workspace.undo(true);
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'Name2', 'type1', 'id1');
             assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
           });
@@ -1612,14 +1688,17 @@ export function testAWorkspace() {
             this.workspace.createVariable('name2', 'type2', 'id2');
             createVarBlocksNoEvents(this.workspace, ['id1', 'id2']);
             this.workspace.renameVariableById('id1', 'Name2');
+            this.clock.runAll();
 
             this.workspace.undo();
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'name1', 'type1', 'id1');
             assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
             assertBlockVarModelName(this.workspace, 0, 'name1');
             assertBlockVarModelName(this.workspace, 1, 'name2');
 
             this.workspace.undo(true);
+            this.clock.runAll();
             assertVariableValues(this.workspace, 'Name2', 'type1', 'id1');
             assertVariableValues(this.workspace, 'name2', 'type2', 'id2');
             assertBlockVarModelName(this.workspace, 0, 'Name2');
diff --git a/tests/mocha/workspace_svg_test.js b/tests/mocha/workspace_svg_test.js
index cea58cdf9..98ca14d57 100644
--- a/tests/mocha/workspace_svg_test.js
+++ b/tests/mocha/workspace_svg_test.js
@@ -21,7 +21,7 @@ import {testAWorkspace} from './test_helpers/workspace.js';
 
 suite('WorkspaceSvg', function () {
   setup(function () {
-    sharedTestSetup.call(this);
+    this.clock = sharedTestSetup.call(this, {fireEventsNow: false}).clock;
     const toolbox = document.getElementById('toolbox-categories');
     this.workspace = Blockly.inject('blocklyDiv', {toolbox: toolbox});
     Blockly.defineBlocksWithJsonArray([
@@ -168,8 +168,7 @@ suite('WorkspaceSvg', function () {
   });
 
   suite('Viewport change events', function () {
-    function resetEventHistory(eventsFireStub, changeListenerSpy) {
-      eventsFireStub.resetHistory();
+    function resetEventHistory(changeListenerSpy) {
       changeListenerSpy.resetHistory();
     }
     function assertSpyFiredViewportEvent(spy, workspace, expectedProperties) {
@@ -187,7 +186,6 @@ suite('WorkspaceSvg', function () {
       );
     }
     function assertViewportEventFired(
-      eventsFireStub,
       changeListenerSpy,
       workspace,
       expectedEventCount = 1,
@@ -200,32 +198,25 @@ suite('WorkspaceSvg', function () {
         viewLeft: metrics.viewLeft,
         type: eventUtils.VIEWPORT_CHANGE,
       };
-      assertSpyFiredViewportEvent(
-        eventsFireStub,
-        workspace,
-        expectedProperties,
-      );
       assertSpyFiredViewportEvent(
         changeListenerSpy,
         workspace,
         expectedProperties,
       );
       sinon.assert.callCount(changeListenerSpy, expectedEventCount);
-      sinon.assert.callCount(eventsFireStub, expectedEventCount);
     }
     function runViewportEventTest(
       eventTriggerFunc,
-      eventsFireStub,
       changeListenerSpy,
       workspace,
       clock,
       expectedEventCount = 1,
     ) {
       clock.runAll();
-      resetEventHistory(eventsFireStub, changeListenerSpy);
+      resetEventHistory(changeListenerSpy);
       eventTriggerFunc();
+      clock.runAll();
       assertViewportEventFired(
-        eventsFireStub,
         changeListenerSpy,
         workspace,
         expectedEventCount,
@@ -243,7 +234,6 @@ suite('WorkspaceSvg', function () {
       test('setScale', function () {
         runViewportEventTest(
           () => this.workspace.setScale(2),
-          this.eventsFireStub,
           this.changeListenerSpy,
           this.workspace,
           this.clock,
@@ -252,7 +242,6 @@ suite('WorkspaceSvg', function () {
       test('zoom(50, 50, 1)', function () {
         runViewportEventTest(
           () => this.workspace.zoom(50, 50, 1),
-          this.eventsFireStub,
           this.changeListenerSpy,
           this.workspace,
           this.clock,
@@ -261,7 +250,6 @@ suite('WorkspaceSvg', function () {
       test('zoom(50, 50, -1)', function () {
         runViewportEventTest(
           () => this.workspace.zoom(50, 50, -1),
-          this.eventsFireStub,
           this.changeListenerSpy,
           this.workspace,
           this.clock,
@@ -270,7 +258,6 @@ suite('WorkspaceSvg', function () {
       test('zoomCenter(1)', function () {
         runViewportEventTest(
           () => this.workspace.zoomCenter(1),
-          this.eventsFireStub,
           this.changeListenerSpy,
           this.workspace,
           this.clock,
@@ -279,7 +266,6 @@ suite('WorkspaceSvg', function () {
       test('zoomCenter(-1)', function () {
         runViewportEventTest(
           () => this.workspace.zoomCenter(-1),
-          this.eventsFireStub,
           this.changeListenerSpy,
           this.workspace,
           this.clock,
@@ -291,7 +277,6 @@ suite('WorkspaceSvg', function () {
         block.render();
         runViewportEventTest(
           () => this.workspace.zoomToFit(),
-          this.eventsFireStub,
           this.changeListenerSpy,
           this.workspace,
           this.clock,
@@ -305,7 +290,6 @@ suite('WorkspaceSvg', function () {
         block.render();
         runViewportEventTest(
           () => this.workspace.centerOnBlock(block.id),
-          this.eventsFireStub,
           this.changeListenerSpy,
           this.workspace,
           this.clock,
@@ -314,7 +298,6 @@ suite('WorkspaceSvg', function () {
       test('scroll', function () {
         runViewportEventTest(
           () => this.workspace.scroll(50, 50),
-          this.eventsFireStub,
           this.changeListenerSpy,
           this.workspace,
           this.clock,
@@ -323,7 +306,6 @@ suite('WorkspaceSvg', function () {
       test('scrollCenter', function () {
         runViewportEventTest(
           () => this.workspace.scrollCenter(),
-          this.eventsFireStub,
           this.changeListenerSpy,
           this.workspace,
           this.clock,
@@ -336,13 +318,12 @@ suite('WorkspaceSvg', function () {
         block.initSvg();
         block.render();
         this.clock.runAll();
-        resetEventHistory(this.eventsFireStub, this.changeListenerSpy);
+        resetEventHistory(this.changeListenerSpy);
         // Expect 2 events, 1 move, 1 viewport
         runViewportEventTest(
           () => {
             block.moveBy(1000, 1000);
           },
-          this.eventsFireStub,
           this.changeListenerSpy,
           this.workspace,
           this.clock,
@@ -366,7 +347,7 @@ suite('WorkspaceSvg', function () {
           '<block type="controls_if" x="188" y="163"></block>',
         );
         this.clock.runAll();
-        resetEventHistory(this.eventsFireStub, this.changeListenerSpy);
+        resetEventHistory(this.changeListenerSpy);
         // Add block in center of other blocks, not triggering scroll.
         Blockly.Xml.domToWorkspace(
           Blockly.utils.xml.textToDom(
@@ -375,11 +356,6 @@ suite('WorkspaceSvg', function () {
           this.workspace,
         );
         this.clock.runAll();
-        assertEventNotFired(
-          this.eventsFireStub,
-          Blockly.Events.ViewportChange,
-          {type: eventUtils.VIEWPORT_CHANGE},
-        );
         assertEventNotFired(
           this.changeListenerSpy,
           Blockly.Events.ViewportChange,
@@ -403,15 +379,10 @@ suite('WorkspaceSvg', function () {
           '<block type="controls_if" x="0" y="0"></block>',
         );
         this.clock.runAll();
-        resetEventHistory(this.eventsFireStub, this.changeListenerSpy);
+        resetEventHistory(this.changeListenerSpy);
         // Add block in center of other blocks, not triggering scroll.
         Blockly.Xml.domToWorkspace(xmlDom, this.workspace);
         this.clock.runAll();
-        assertEventNotFired(
-          this.eventsFireStub,
-          Blockly.Events.ViewportChange,
-          {type: eventUtils.VIEWPORT_CHANGE},
-        );
         assertEventNotFired(
           this.changeListenerSpy,
           Blockly.Events.ViewportChange,
@@ -436,7 +407,6 @@ suite('WorkspaceSvg', function () {
         // Expect 10 events, 4 create, 4 move, 1 viewport, 1 finished loading
         runViewportEventTest(
           addingMultipleBlocks,
-          this.eventsFireStub,
           this.changeListenerSpy,
           this.workspace,
           this.clock,