diff --git a/packages/app-layout/test/app-layout.test.js b/packages/app-layout/test/app-layout.test.js
index 102554389b..81db7b147a 100644
--- a/packages/app-layout/test/app-layout.test.js
+++ b/packages/app-layout/test/app-layout.test.js
@@ -6,31 +6,13 @@ import {
   makeSoloTouchEvent,
   nextFrame,
   nextRender,
+  nextResize,
   oneEvent,
 } from '@vaadin/testing-helpers';
 import sinon from 'sinon';
 import '../vaadin-app-layout.js';
 import '../vaadin-drawer-toggle.js';
-
-/**
- * Resolves once the function is invoked on the given object.
- */
-function onceInvoked(object, functionName) {
-  return new Promise((resolve) => {
-    sinon.replace(object, functionName, (...args) => {
-      sinon.restore();
-      object[functionName](...args);
-      resolve();
-    });
-  });
-}
-
-/**
- * Resolves once the ResizeObserver has processed a resize.
- */
-async function onceResized(layout) {
-  await onceInvoked(layout, '_updateOffsetSize');
-}
+import './not-animated-styles.js';
 
 describe('vaadin-app-layout', () => {
   let layout;
@@ -110,12 +92,12 @@ describe('vaadin-app-layout', () => {
         navbarContent.style.height = '100px';
         navbarContent.setAttribute('slot', 'navbar');
         layout.appendChild(navbarContent);
-        await onceResized(layout);
+        await nextResize(layout);
         const initialOffset = parseInt(getComputedStyle(layout).getPropertyValue('padding-top'));
         expect(initialOffset).to.be.greaterThan(0);
         // Increase navbar content size and measure increase
         navbarContent.style.height = '200px';
-        await onceResized(layout);
+        await nextResize(layout);
         const updatedOffset = parseInt(getComputedStyle(layout).getPropertyValue('padding-top'));
         expect(updatedOffset).to.equal(initialOffset + 100);
       });
@@ -164,12 +146,12 @@ describe('vaadin-app-layout', () => {
         navbarContent.style.height = '100px';
         navbarContent.setAttribute('slot', 'navbar touch-optimized');
         layout.appendChild(navbarContent);
-        await onceResized(layout);
+        await nextResize(layout);
         const initialOffset = parseInt(getComputedStyle(layout).getPropertyValue('padding-bottom'));
         expect(initialOffset).to.be.greaterThan(0);
         // Increase navbar content size and measure increase
         navbarContent.style.height = '200px';
-        await onceResized(layout);
+        await nextResize(layout);
         const updatedOffset = parseInt(getComputedStyle(layout).getPropertyValue('padding-bottom'));
         expect(updatedOffset).to.equal(initialOffset + 100);
       });
@@ -198,7 +180,7 @@ describe('vaadin-app-layout', () => {
       drawer = layout.shadowRoot.querySelector('[part=drawer]');
       backdrop = layout.shadowRoot.querySelector('[part=backdrop]');
       // Wait for the initial resize observer callback
-      await onceResized(layout);
+      await nextResize(layout);
       await nextFrame();
     }
 
@@ -291,7 +273,7 @@ describe('vaadin-app-layout', () => {
 
       it('should only update offset size once during the drawer transition', async () => {
         layout.primarySection = 'drawer';
-        await onceResized(layout);
+        await nextResize(layout);
         await nextRender();
 
         layout.style.setProperty('--vaadin-app-layout-transition', '100ms');
diff --git a/packages/app-layout/test/not-animated-styles.js b/packages/app-layout/test/not-animated-styles.js
new file mode 100644
index 0000000000..5d98ef6ac0
--- /dev/null
+++ b/packages/app-layout/test/not-animated-styles.js
@@ -0,0 +1,10 @@
+import { css, registerStyles } from '@vaadin/vaadin-themable-mixin/vaadin-themable-mixin.js';
+
+registerStyles(
+  'vaadin-app-layout',
+  css`
+    :host {
+      transition: none !important;
+    }
+  `,
+);
diff --git a/packages/avatar-group/test/avatar-group.test.js b/packages/avatar-group/test/avatar-group.test.js
index ab24172d80..f06599287a 100644
--- a/packages/avatar-group/test/avatar-group.test.js
+++ b/packages/avatar-group/test/avatar-group.test.js
@@ -4,6 +4,7 @@ import {
   escKeyDown,
   fixtureSync,
   nextRender,
+  nextResize,
   oneEvent,
   spaceKeyDown,
   tabKeyDown,
@@ -11,26 +12,6 @@ import {
 import sinon from 'sinon';
 import '../vaadin-avatar-group.js';
 
-/**
- * Resolves once the function is invoked on the given object.
- */
-function onceInvoked(object, functionName) {
-  return new Promise((resolve) => {
-    sinon.replace(object, functionName, (...args) => {
-      sinon.restore();
-      object[functionName](...args);
-      resolve();
-    });
-  });
-}
-
-/**
- * Resolves once the ResizeObserver in AvatarGroup has processed a resize.
- */
-async function onceResized(group) {
-  await onceInvoked(group, '__setItemsInView');
-}
-
 describe('avatar-group', () => {
   let group;
 
@@ -189,7 +170,7 @@ describe('avatar-group', () => {
 
       it('should consider element width when maxItemsVisible is set', async () => {
         group.style.width = '100px';
-        await onceResized(group);
+        await nextResize(group);
 
         const items = group.querySelectorAll('vaadin-avatar');
         expect(items.length).to.equal(3);
@@ -197,7 +178,7 @@ describe('avatar-group', () => {
 
       it('should set abbr property correctly if maxItemsVisible and width are set', async () => {
         group.style.width = '100px';
-        await onceResized(group);
+        await nextResize(group);
 
         const overflow = group._overflow;
         expect(overflow.abbr).to.equal('+3');
@@ -217,7 +198,7 @@ describe('avatar-group', () => {
 
     it('should render avatars to fit width on resize', async () => {
       group.style.width = '110px';
-      await onceResized(group);
+      await nextResize(group);
       const items = group.querySelectorAll('vaadin-avatar');
       expect(items.length).to.equal(3);
       expect(overflow.abbr).to.equal('+3');
@@ -226,27 +207,27 @@ describe('avatar-group', () => {
     it('should always show at least two avatars', async () => {
       group.set('items', group.items.slice(0, 2));
       group.style.width = '50px';
-      await onceResized(group);
+      await nextResize(group);
       const items = group.querySelectorAll('vaadin-avatar:not([hidden])');
       expect(items.length).to.equal(2);
     });
 
     it('should not show overlay with only one avatar', async () => {
       group.style.width = '170px';
-      await onceResized(group);
+      await nextResize(group);
       expect(overflow.hasAttribute('hidden')).to.be.true;
     });
 
     it('should re-render avatars on items change', async () => {
       group.style.width = '110px';
       group.items = group.items.slice(0, 2);
-      await onceResized(group);
+      await nextResize(group);
       expect(overflow.hasAttribute('hidden')).to.be.true;
     });
 
     it('should render avatars in the menu items', async () => {
       group.style.width = '110px';
-      await onceResized(group);
+      await nextResize(group);
 
       overflow.click();
       await oneEvent(overlay, 'vaadin-overlay-open');
@@ -257,13 +238,13 @@ describe('avatar-group', () => {
 
     it('should re-render overflowing avatars on resize', async () => {
       group.style.width = '110px';
-      await onceResized(group);
+      await nextResize(group);
 
       overflow.click();
       await oneEvent(overlay, 'vaadin-overlay-open');
 
       group.style.width = '75px';
-      await onceResized(group);
+      await nextResize(group);
 
       const items = overlay.querySelectorAll('vaadin-avatar-group-menu-item');
       expect(items.length).to.equal(4);
@@ -271,13 +252,13 @@ describe('avatar-group', () => {
 
     it('should close overlay on resize when all avatars fit', async () => {
       group.style.width = '110px';
-      await onceResized(group);
+      await nextResize(group);
 
       overflow.click();
       await oneEvent(overlay, 'vaadin-overlay-open');
 
       group.style.width = '';
-      await onceResized(group);
+      await nextResize(group);
 
       expect(overlay.opened).to.be.false;
     });
diff --git a/packages/board/test/helpers.js b/packages/board/test/helpers.js
index c87111574c..8172229274 100644
--- a/packages/board/test/helpers.js
+++ b/packages/board/test/helpers.js
@@ -1,28 +1,8 @@
-import sinon from 'sinon';
-
-/**
- * Resolves once the function is invoked on the given object.
- */
-function onceInvoked(object, functionName) {
-  return new Promise((resolve) => {
-    const stub = sinon.stub(object, functionName).callsFake((...args) => {
-      stub.restore();
-      object[functionName](...args);
-      resolve();
-    });
-  });
-}
-
-/**
- * Resolves once the ResizeObserver in BoardRow has processed a resize.
- */
-export async function onceResized(boardRow) {
-  await onceInvoked(boardRow, '_onResize');
-}
+import { nextResize } from '@vaadin/testing-helpers';
 
 /**
  * Resolves once the ResizeObserver in all the BoardRows has processed a resize.
  */
 export function allResized(boardRows) {
-  return Promise.all(boardRows.map((boardRow) => onceResized(boardRow)));
+  return Promise.all(boardRows.map((boardRow) => nextResize(boardRow)));
 }
diff --git a/packages/board/test/redraw.test.js b/packages/board/test/redraw.test.js
index 1e93e8c06b..eceff24b25 100644
--- a/packages/board/test/redraw.test.js
+++ b/packages/board/test/redraw.test.js
@@ -1,7 +1,7 @@
 import { expect } from '@vaadin/chai-plugins';
-import { aTimeout, fixtureSync } from '@vaadin/testing-helpers';
+import { aTimeout, fixtureSync, nextResize } from '@vaadin/testing-helpers';
 import '../vaadin-board.js';
-import { allResized, onceResized } from './helpers.js';
+import { allResized } from './helpers.js';
 
 describe('redraw', () => {
   describe('board', () => {
@@ -19,7 +19,7 @@ describe('redraw', () => {
         </vaadin-board>
       `);
       row = board.firstElementChild;
-      await onceResized(row);
+      await nextResize(row);
     });
 
     it('should trigger layout after board style is changed', () => {
@@ -49,7 +49,7 @@ describe('redraw', () => {
           <div>top D</div>
         </vaadin-board-row>
       `);
-      await onceResized(row);
+      await nextResize(row);
     });
 
     it('should trigger layout after board row style is changed', () => {
@@ -85,7 +85,7 @@ describe('redraw', () => {
       `);
       row = board.querySelector('#nested');
 
-      await onceResized(row);
+      await nextResize(row);
     });
 
     it('should trigger layout for nested rows after board style is changed', () => {
@@ -199,7 +199,7 @@ describe('redraw', () => {
       expect(first.className).to.equal('');
 
       container.style.width = '1001px';
-      await onceResized(first);
+      await nextResize(first);
       expect(first.className).to.equal('large');
     });
 
diff --git a/packages/charts/test/chart-element.test.js b/packages/charts/test/chart-element.test.js
index 44f228475b..197f7d2f93 100644
--- a/packages/charts/test/chart-element.test.js
+++ b/packages/charts/test/chart-element.test.js
@@ -1,29 +1,8 @@
 import { expect } from '@vaadin/chai-plugins';
-import { aTimeout, fixtureSync, nextFrame, nextRender, oneEvent } from '@vaadin/testing-helpers';
+import { aTimeout, fixtureSync, nextFrame, nextRender, nextResize, oneEvent } from '@vaadin/testing-helpers';
 import sinon from 'sinon';
 import '../vaadin-chart.js';
 
-/**
- * Resolves once the function is invoked on the given object.
- */
-function onceInvoked(object, functionName) {
-  return new Promise((resolve) => {
-    sinon.replace(object, functionName, (...args) => {
-      sinon.restore();
-      object[functionName](...args);
-      resolve();
-    });
-  });
-}
-
-/**
- * Resolves once the ResizeObserver in AvatarGroup has processed a resize.
- */
-async function onceResized(el) {
-  // Wait for the _onResize function to be invoked by the ResizeObserver
-  await onceInvoked(el, '_onResize');
-}
-
 describe('vaadin-chart', () => {
   describe('custom element definition', () => {
     let chart, tagName;
@@ -346,7 +325,7 @@ describe('vaadin-chart', () => {
       expect(charts[1].configuration.chartWidth).to.be.equal(500);
 
       layout.style.width = '500px';
-      await onceResized(charts[0]);
+      await nextResize(charts[0]);
 
       expect(layout.getBoundingClientRect().width).to.be.equal(500);
       expect(charts[0].configuration.chartWidth).to.be.equal(250);
@@ -359,7 +338,7 @@ describe('vaadin-chart', () => {
       expect(charts[1].configuration.chartHeight).to.be.equal(300);
 
       layout.style.height = '200px';
-      await onceResized(charts[0]);
+      await nextResize(charts[0]);
 
       expect(layout.getBoundingClientRect().height).to.be.equal(200);
       expect(charts[0].configuration.chartHeight).to.be.equal(200);
diff --git a/packages/component-base/test/overflow-controller.test.js b/packages/component-base/test/overflow-controller.test.js
index 61ae8792d5..624b7e5fb9 100644
--- a/packages/component-base/test/overflow-controller.test.js
+++ b/packages/component-base/test/overflow-controller.test.js
@@ -1,30 +1,9 @@
 import { expect } from '@vaadin/chai-plugins';
-import { fixtureSync, nextFrame, nextRender } from '@vaadin/testing-helpers';
-import sinon from 'sinon';
+import { fixtureSync, nextFrame, nextRender, nextResize } from '@vaadin/testing-helpers';
 import { html, PolymerElement } from '@polymer/polymer/polymer-element.js';
 import { ControllerMixin } from '../src/controller-mixin.js';
 import { OverflowController } from '../src/overflow-controller.js';
 
-/**
- * Resolves once the function is invoked on the given object.
- */
-function onceInvoked(object, functionName) {
-  return new Promise((resolve) => {
-    sinon.replace(object, functionName, (...args) => {
-      sinon.restore();
-      object[functionName](...args);
-      resolve();
-    });
-  });
-}
-
-/**
- * Resolves once the ResizeObserver has processed a resize.
- */
-async function onceResized(controller) {
-  await onceInvoked(controller, '__updateOverflow');
-}
-
 customElements.define(
   'overflow-element',
   class OverflowElement extends ControllerMixin(PolymerElement) {
@@ -124,7 +103,7 @@ describe('overflow-controller', () => {
           describe(`small viewport ${dir}`, () => {
             beforeEach(async () => {
               element.style.width = '80px';
-              await onceResized(controller);
+              await nextResize(element);
               await nextFrame();
             });
 
@@ -147,7 +126,8 @@ describe('overflow-controller', () => {
 
             it(`should update overflow attribute on host resize with ${dir}`, async () => {
               element.style.width = 'auto';
-              await onceResized(controller);
+              await nextResize(element);
+              await nextFrame();
               expect(element.hasAttribute('overflow')).to.be.false;
             });
 
@@ -155,7 +135,8 @@ describe('overflow-controller', () => {
               items.forEach((item) => {
                 item.style.minWidth = '20px';
               });
-              await onceResized(controller);
+              await Promise.all(items.map((item) => nextResize(item)));
+              await nextFrame();
               expect(element.hasAttribute('overflow')).to.be.false;
             });
 
@@ -177,7 +158,8 @@ describe('overflow-controller', () => {
               await nextFrame();
 
               div.style.minWidth = '30px';
-              await onceResized(controller);
+              await nextResize(div);
+              await nextFrame();
               expect(element.hasAttribute('overflow')).to.be.true;
             });
           });
@@ -211,7 +193,7 @@ describe('overflow-controller', () => {
       describe('small viewport', () => {
         beforeEach(async () => {
           element.style.height = '80px';
-          await onceResized(controller);
+          await nextResize(element);
           await nextFrame();
         });
 
@@ -234,7 +216,8 @@ describe('overflow-controller', () => {
 
         it('should update overflow attribute on host element resize', async () => {
           element.style.height = 'auto';
-          await onceResized(controller);
+          await nextResize(element);
+          await nextFrame();
           expect(element.hasAttribute('overflow')).to.be.false;
         });
 
@@ -242,7 +225,8 @@ describe('overflow-controller', () => {
           items.forEach((item) => {
             item.style.height = '15px';
           });
-          await onceResized(controller);
+          await Promise.all(items.map((item) => nextResize(item)));
+          await nextFrame();
           expect(element.hasAttribute('overflow')).to.be.false;
         });
 
@@ -280,7 +264,7 @@ describe('overflow-controller', () => {
       beforeEach(async () => {
         element.style.width = '80px';
         scroller.style.display = 'flex';
-        await onceResized(controller);
+        await nextResize(element);
         await nextFrame();
       });
 
@@ -294,7 +278,7 @@ describe('overflow-controller', () => {
     describe('vertical scroller', () => {
       beforeEach(async () => {
         element.style.height = '80px';
-        await onceResized(controller);
+        await nextResize(element);
         await nextFrame();
       });
 
diff --git a/packages/component-base/test/resize-mixin.test.js b/packages/component-base/test/resize-mixin.test.js
index 5743eb99f1..b964848195 100644
--- a/packages/component-base/test/resize-mixin.test.js
+++ b/packages/component-base/test/resize-mixin.test.js
@@ -1,30 +1,9 @@
 import { expect } from '@vaadin/chai-plugins';
-import { aTimeout, fixtureSync, nextFrame } from '@vaadin/testing-helpers';
+import { aTimeout, fixtureSync, nextFrame, nextResize } from '@vaadin/testing-helpers';
 import sinon from 'sinon';
 import { html, PolymerElement } from '@polymer/polymer/polymer-element.js';
 import { ResizeMixin } from '../src/resize-mixin.js';
 
-/**
- * Resolves once the function is invoked on the given object.
- */
-function onceInvoked(object, functionName) {
-  return new Promise((resolve) => {
-    sinon.replace(object, functionName, (...args) => {
-      sinon.restore();
-      object[functionName](...args);
-      resolve();
-    });
-  });
-}
-
-/**
- * Resolves once the ResizeObserver in AvatarGroup has processed a resize.
- */
-async function onceResized(el) {
-  // Wait for the _onResize function to be invoked by the ResizeObserver
-  await onceInvoked(el, '_onResize');
-}
-
 describe('resize-mixin', () => {
   let element, observeParent;
 
@@ -53,13 +32,13 @@ describe('resize-mixin', () => {
   beforeEach(async () => {
     element = fixtureSync(`<resize-mixin-element></resize-mixin-element>`);
     // Wait for the initial resize.
-    await onceResized(element);
+    await nextResize(element);
   });
 
   it('should notify resize', async () => {
     const spy = sinon.spy(element, '_onResize');
     element.style.width = '100px';
-    await onceResized(element);
+    await nextResize(element);
     expect(spy.calledOnce).to.be.true;
   });
 
@@ -83,13 +62,13 @@ describe('resize-mixin', () => {
       beforeEach(async () => {
         parent.appendChild(element);
         // Wait for the initial resize.
-        await onceResized(element);
+        await nextResize(parent);
       });
 
       it('should notify parent element resize', async () => {
         const spy = sinon.spy(element, '_onResize');
         parent.style.width = '100px';
-        await onceResized(element);
+        await nextResize(parent);
         expect(spy.calledOnce).to.be.true;
       });
 
@@ -130,13 +109,13 @@ describe('resize-mixin', () => {
         parent.attachShadow({ mode: 'open' });
         parent.shadowRoot.appendChild(element);
         // Wait for the initial resize.
-        await onceResized(element);
+        await nextResize(parent);
       });
 
       it('should notify shadow host resize', async () => {
         const spy = sinon.spy(element, '_onResize');
         parent.style.width = '100px';
-        await onceResized(element);
+        await nextResize(parent);
         expect(spy.calledOnce).to.be.true;
       });
     });
diff --git a/packages/dialog/test/header-footer.common.js b/packages/dialog/test/header-footer.common.js
index 04869336c7..9e7e9bd91d 100644
--- a/packages/dialog/test/header-footer.common.js
+++ b/packages/dialog/test/header-footer.common.js
@@ -1,5 +1,5 @@
 import { expect } from '@vaadin/chai-plugins';
-import { fixtureSync, nextRender, nextUpdate } from '@vaadin/testing-helpers';
+import { fixtureSync, nextRender, nextResize, nextUpdate } from '@vaadin/testing-helpers';
 import sinon from 'sinon';
 import { createRenderer } from './helpers.js';
 
@@ -489,12 +489,6 @@ describe('header/footer feature', () => {
     });
 
     describe('resize', () => {
-      const nextResize = (target) => {
-        return new Promise((resolve) => {
-          new ResizeObserver(() => setTimeout(resolve)).observe(target);
-        });
-      };
-
       it('should not set overflow attribute when content has no scrollbar', () => {
         expect(overlay.hasAttribute('overflow')).to.be.false;
       });
diff --git a/packages/form-layout/test/form-layout.test.js b/packages/form-layout/test/form-layout.test.js
index 7616fdbe3c..f0fc741949 100644
--- a/packages/form-layout/test/form-layout.test.js
+++ b/packages/form-layout/test/form-layout.test.js
@@ -1,5 +1,5 @@
 import { expect } from '@vaadin/chai-plugins';
-import { aTimeout, fixtureSync, nextFrame, nextRender } from '@vaadin/testing-helpers';
+import { aTimeout, fixtureSync, nextFrame, nextRender, nextResize } from '@vaadin/testing-helpers';
 import sinon from 'sinon';
 import '@polymer/polymer/lib/elements/dom-repeat.js';
 import '@vaadin/text-field/vaadin-text-field.js';
@@ -7,26 +7,6 @@ import '../vaadin-form-layout.js';
 import '../vaadin-form-item.js';
 import { html, PolymerElement } from '@polymer/polymer/polymer-element.js';
 
-/**
- * Resolves once the function is invoked on the given object.
- */
-function onceInvoked(object, functionName) {
-  return new Promise((resolve) => {
-    sinon.replace(object, functionName, (...args) => {
-      sinon.restore();
-      object[functionName](...args);
-      resolve();
-    });
-  });
-}
-
-/**
- * Resolves once the ResizeObserver in FormLayout has processed a resize.
- */
-async function onceResized(layout) {
-  await onceInvoked(layout, '_updateLayout');
-}
-
 customElements.define(
   'mutable-layout',
   class extends PolymerElement {
@@ -150,7 +130,7 @@ describe('form layout', () => {
     it('should apply default column-spacing', async () => {
       // Override to not depend on the theme changes
       layout.style.setProperty('--lumo-space-l', '2rem');
-      await onceResized(layout);
+      await nextResize(layout);
       expect(getParsedWidth(layout.firstElementChild).spacing).to.equal('1rem');
       expect(getComputedStyle(layout.firstElementChild).getPropertyValue('margin-left')).to.equal('0px'); // Zero because it's first
       expect(getComputedStyle(layout.firstElementChild).getPropertyValue('margin-right')).to.equal('16px'); // 0.5 * 2rem in px
@@ -353,17 +333,17 @@ describe('form layout', () => {
 
       it('should be responsive by default', async () => {
         document.body.style.width = '10em';
-        await onceResized(layout);
+        await nextResize(layout);
         expect(estimateEffectiveColumnCount(layout)).to.be.closeTo(1, 0.1);
         expect(layout.children[2].getAttribute('label-position')).to.equal('top');
 
         document.body.style.width = '20em';
-        await onceResized(layout);
+        await nextResize(layout);
         expect(estimateEffectiveColumnCount(layout)).to.be.closeTo(1, 0.1);
         expect(layout.children[2].getAttribute('label-position')).to.be.null;
 
         document.body.style.width = '40em';
-        await onceResized(layout);
+        await nextResize(layout);
         expect(estimateEffectiveColumnCount(layout)).to.be.closeTo(2, 0.1);
         expect(layout.children[2].getAttribute('label-position')).to.be.null;
       });
@@ -395,17 +375,17 @@ describe('form layout', () => {
         ];
 
         document.body.style.width = '10em';
-        await onceResized(layout);
+        await nextResize(layout);
         expect(estimateEffectiveColumnCount(layout)).to.be.closeTo(1, 0.1);
         expect(layout.children[2].getAttribute('label-position')).to.be.null;
 
         document.body.style.width = '20em';
-        await onceResized(layout);
+        await nextResize(layout);
         expect(estimateEffectiveColumnCount(layout)).to.be.closeTo(2, 0.1);
         expect(layout.children[2].getAttribute('label-position')).to.equal('top');
 
         document.body.style.width = '40em';
-        await onceResized(layout);
+        await nextResize(layout);
         expect(estimateEffectiveColumnCount(layout)).to.be.closeTo(5, 0.1);
         expect(layout.children[2].getAttribute('label-position')).to.be.null;
       });
diff --git a/packages/grid/test/column-groups.common.js b/packages/grid/test/column-groups.common.js
index be47950c48..56956acd71 100644
--- a/packages/grid/test/column-groups.common.js
+++ b/packages/grid/test/column-groups.common.js
@@ -1,5 +1,5 @@
 import { expect } from '@vaadin/chai-plugins';
-import { fixtureSync, nextFrame, nextRender } from '@vaadin/testing-helpers';
+import { fixtureSync, nextFrame, nextRender, nextResize } from '@vaadin/testing-helpers';
 import sinon from 'sinon';
 import {
   attributeRenderer,
@@ -9,7 +9,6 @@ import {
   getRowCells,
   getRows,
   infiniteDataProvider,
-  nextResize,
   scrollToEnd,
 } from './helpers.js';
 
diff --git a/packages/grid/test/column-rendering.common.js b/packages/grid/test/column-rendering.common.js
index fb20302330..7b125bfb93 100644
--- a/packages/grid/test/column-rendering.common.js
+++ b/packages/grid/test/column-rendering.common.js
@@ -1,7 +1,7 @@
 import { expect } from '@vaadin/chai-plugins';
-import { aTimeout, fixtureSync, keyDownOn, nextFrame, oneEvent } from '@vaadin/testing-helpers';
+import { aTimeout, fixtureSync, keyDownOn, nextFrame, nextResize, oneEvent } from '@vaadin/testing-helpers';
 import Sinon from 'sinon';
-import { flushGrid, getCellContent, getHeaderCellContent, onceResized } from './helpers.js';
+import { flushGrid, getCellContent, getHeaderCellContent } from './helpers.js';
 
 ['ltr', 'rtl'].forEach((dir) => {
   describe(`lazy column rendering - ${dir}`, () => {
@@ -99,7 +99,7 @@ import { flushGrid, getCellContent, getHeaderCellContent, onceResized } from './
 
       grid.columnRendering = 'lazy';
       // Wait for the initial resize observer callback
-      await onceResized(grid);
+      await nextResize(grid);
       flushGrid(grid);
     });
 
@@ -141,7 +141,7 @@ import { flushGrid, getCellContent, getHeaderCellContent, onceResized } from './
 
     it('should render columns revealed columns on resize', async () => {
       grid.style.width = `${grid.$.table.scrollWidth}px`;
-      await onceResized(grid);
+      await nextResize(grid);
       expectBodyCellUpdated(getLastVisibleColumnIndex());
       expectBodyCellUpdated(columns.length - 1);
     });
@@ -222,7 +222,7 @@ import { flushGrid, getCellContent, getHeaderCellContent, onceResized } from './
         </vaadin-grid>
       `);
       grid.items = [{ name: `Item 1` }];
-      await onceResized(grid);
+      await nextResize(grid);
       flushGrid(grid);
 
       const newColumn = document.createElement('vaadin-grid-column');
@@ -278,7 +278,7 @@ import { flushGrid, getCellContent, getHeaderCellContent, onceResized } from './
 
       it('should render columns revealed columns on resize', async () => {
         grid.style.width = `${grid.$.table.scrollWidth}px`;
-        await onceResized(grid);
+        await nextResize(grid);
         expectBodyCellUpdated(0);
         expectBodyCellUpdated(1);
       });
diff --git a/packages/grid/test/frozen-columns.common.js b/packages/grid/test/frozen-columns.common.js
index 5daae787eb..90ce1eb94a 100644
--- a/packages/grid/test/frozen-columns.common.js
+++ b/packages/grid/test/frozen-columns.common.js
@@ -1,17 +1,10 @@
 import { expect } from '@vaadin/chai-plugins';
-import { fixtureSync, listenOnce, nextRender } from '@vaadin/testing-helpers';
+import { fixtureSync, listenOnce, nextRender, nextResize } from '@vaadin/testing-helpers';
 import { resetMouse, sendMouse } from '@web/test-runner-commands';
 import sinon from 'sinon';
 import { isElementFocused } from '@vaadin/a11y-base/src/focus-utils.js';
 import { setNormalizedScrollLeft } from '@vaadin/component-base/src/dir-utils.js';
-import {
-  flushGrid,
-  getRowCells,
-  getRows,
-  infiniteDataProvider,
-  isWithinParentConstraints,
-  onceResized,
-} from './helpers.js';
+import { flushGrid, getRowCells, getRows, infiniteDataProvider, isWithinParentConstraints } from './helpers.js';
 
 // Returns true if the element's computed transform style matches with the
 // computed transform style of a div element with the given transform applied
@@ -296,7 +289,7 @@ const frozenGridFixture = (frozen, frozenToEnd) => {
           const x = cells[2].getBoundingClientRect().x;
 
           grid.style.width = '300px';
-          await onceResized(grid);
+          await nextResize(grid);
 
           expect(cells[2].getBoundingClientRect().x).to.equal(isRTL ? x - 100 : x + 100);
         });
@@ -326,7 +319,7 @@ const frozenGridFixture = (frozen, frozenToEnd) => {
           grid._columnTree[0][frozenToEndColumnIndex].flexGrow = 0;
 
           grid.style.width = '400px';
-          await onceResized(grid);
+          await nextResize(grid);
 
           const initBoundingClientRect = getRowCells(containerRows[0])[2].getBoundingClientRect();
 
@@ -347,7 +340,7 @@ const frozenGridFixture = (frozen, frozenToEnd) => {
           grid._columnTree[0][frozenToEndColumnIndex].flexGrow = 0;
 
           grid.style.width = '400px';
-          await onceResized(grid);
+          await nextResize(grid);
 
           for (let i = 0; i < 2; i++) {
             if (frozenToEndColumnIndex === i) {
diff --git a/packages/grid/test/helpers.js b/packages/grid/test/helpers.js
index 63f252fc21..a219332c4e 100644
--- a/packages/grid/test/helpers.js
+++ b/packages/grid/test/helpers.js
@@ -1,4 +1,3 @@
-import { aTimeout } from '@vaadin/testing-helpers';
 import sinon from 'sinon';
 
 export const flushGrid = (grid) => {
@@ -262,12 +261,6 @@ export const makeSoloTouchEvent = (type, xy, node) => {
   return event;
 };
 
-export const nextResize = (target) => {
-  return new Promise((resolve) => {
-    new ResizeObserver(() => setTimeout(resolve)).observe(target);
-  });
-};
-
 /**
  * Resolves once the function is invoked on the given object.
  */
@@ -281,15 +274,6 @@ export function onceInvoked(object, functionName) {
   });
 }
 
-/**
- * Resolves once the ResizeObserver in grid has processed a resize.
- */
-export async function onceResized(grid) {
-  await onceInvoked(grid, '_onResize');
-  // Grid's resize observer uses setTimeout
-  await aTimeout(0);
-}
-
 export const shiftClick = (node) => {
   node.dispatchEvent(new MouseEvent('click', { shiftKey: true }));
 };
diff --git a/packages/grid/test/resizing.common.js b/packages/grid/test/resizing.common.js
index 9a4cd214d4..34a8c168c9 100644
--- a/packages/grid/test/resizing.common.js
+++ b/packages/grid/test/resizing.common.js
@@ -1,5 +1,5 @@
 import { expect } from '@vaadin/chai-plugins';
-import { aTimeout, fixtureSync, nextFrame, oneEvent } from '@vaadin/testing-helpers';
+import { aTimeout, fixtureSync, nextFrame, nextResize, oneEvent } from '@vaadin/testing-helpers';
 import sinon from 'sinon';
 import { html, PolymerElement } from '@polymer/polymer/polymer-element.js';
 import {
@@ -11,7 +11,6 @@ import {
   getRowCells,
   getRows,
   infiniteDataProvider,
-  nextResize,
   scrollToEnd,
 } from './helpers.js';
 
diff --git a/packages/grid/test/scrolling-mode.common.js b/packages/grid/test/scrolling-mode.common.js
index 77fcd7bb7c..705b989539 100644
--- a/packages/grid/test/scrolling-mode.common.js
+++ b/packages/grid/test/scrolling-mode.common.js
@@ -1,6 +1,14 @@
 import { expect } from '@vaadin/chai-plugins';
-import { fixtureSync, isDesktopSafari, isFirefox, listenOnce, nextFrame, nextRender } from '@vaadin/testing-helpers';
-import { flushGrid, infiniteDataProvider, onceResized, scrollToEnd } from './helpers.js';
+import {
+  fixtureSync,
+  isDesktopSafari,
+  isFirefox,
+  listenOnce,
+  nextFrame,
+  nextRender,
+  nextResize,
+} from '@vaadin/testing-helpers';
+import { flushGrid, infiniteDataProvider, scrollToEnd } from './helpers.js';
 
 describe('scrolling mode', () => {
   let grid;
@@ -105,12 +113,12 @@ describe('scrolling mode', () => {
     // but not as often as in WebKit.
     (isDesktopSafari || isFirefox ? it.skip : it)('update on resize', async () => {
       grid.style.width = '200px';
-      await onceResized(grid);
+      await nextResize(grid);
       await nextFrame();
       expect(grid.getAttribute('overflow')).to.equal('bottom');
 
       grid.style.width = '50px';
-      await onceResized(grid);
+      await nextResize(grid);
       await nextFrame();
       expect(grid.getAttribute('overflow')).to.equal('bottom end right');
     });
diff --git a/packages/icon/test/icon-font.common.js b/packages/icon/test/icon-font.common.js
index 8f610d18e7..b49a066e8a 100644
--- a/packages/icon/test/icon-font.common.js
+++ b/packages/icon/test/icon-font.common.js
@@ -1,31 +1,8 @@
 import { expect } from '@vaadin/chai-plugins';
-import { fixtureSync, isChrome, nextFrame } from '@vaadin/testing-helpers';
-import sinon from 'sinon';
+import { fixtureSync, isChrome, nextFrame, nextResize } from '@vaadin/testing-helpers';
 import { needsFontIconSizingFallback, supportsCQUnitsForPseudoElements } from '../src/vaadin-icon-helpers.js';
 import { iconFontCss } from './test-icon-font.js';
 
-/**
- * Resolves once the function is invoked on the given object.
- */
-function onceInvoked(object, functionName) {
-  return new Promise((resolve) => {
-    sinon.replace(object, functionName, (...args) => {
-      sinon.restore();
-      object[functionName](...args);
-      resolve();
-    });
-  });
-}
-
-/**
- * Resolves once the icon resize is complete.
- */
-async function onceResized(icon) {
-  if (needsFontIconSizingFallback()) {
-    await onceInvoked(icon, '_onResize');
-  }
-}
-
 describe('vaadin-icon - icon fonts', () => {
   beforeEach(() => {
     fixtureSync(`
@@ -40,7 +17,7 @@ describe('vaadin-icon - icon fonts', () => {
 
     beforeEach(async () => {
       icon = fixtureSync('<vaadin-icon icon-class="my-icon-font icon-before"></vaadin-icon>');
-      await onceResized(icon);
+      await nextResize(icon);
     });
 
     it('should have the same height as the host', () => {
@@ -51,7 +28,7 @@ describe('vaadin-icon - icon fonts', () => {
     it('should resize with the host', async () => {
       icon.style.width = '100px';
       icon.style.height = '100px';
-      await onceResized(icon);
+      await nextResize(icon);
       const fontIconStyle = getComputedStyle(icon, ':before');
       expect(parseInt(fontIconStyle.height)).to.be.closeTo(100, 1);
     });
@@ -59,7 +36,7 @@ describe('vaadin-icon - icon fonts', () => {
     it('should not overflow host - wider icon', async () => {
       icon.style.width = '150px';
       icon.style.height = '100px';
-      await onceResized(icon);
+      await nextResize(icon);
       const fontIconStyle = getComputedStyle(icon, ':before');
       expect(parseInt(fontIconStyle.height)).to.be.closeTo(100, 1);
     });
@@ -71,11 +48,11 @@ describe('vaadin-icon - icon fonts', () => {
 
     it('should subtract vertical padding from height', async () => {
       icon.style.padding = '5px';
-      await onceResized(icon);
+      await nextResize(icon);
       expect(parseInt(getComputedStyle(icon, ':before').height)).to.be.closeTo(14, 1);
 
       icon.style.padding = '7px';
-      await onceResized(icon);
+      await nextResize(icon);
       expect(parseInt(getComputedStyle(icon, ':before').height)).to.be.closeTo(10, 1);
     });
   });
@@ -333,7 +310,7 @@ describe('vaadin-icon - icon fonts', () => {
       await nextFrame();
       icon.style.width = '100px';
       icon.style.height = '100px';
-      await onceResized(icon);
+      await nextResize(icon);
       expect(icon.style.getPropertyValue('--_vaadin-font-icon-size')).to.equal('100px');
     });
 
diff --git a/packages/menu-bar/test/overflow.common.js b/packages/menu-bar/test/overflow.common.js
index c5a3d5da41..092f712d6e 100644
--- a/packages/menu-bar/test/overflow.common.js
+++ b/packages/menu-bar/test/overflow.common.js
@@ -1,6 +1,5 @@
 import { expect } from '@vaadin/chai-plugins';
-import { arrowRight, fixtureSync, nextFrame, nextRender, nextUpdate } from '@vaadin/testing-helpers';
-import sinon from 'sinon';
+import { arrowRight, fixtureSync, nextFrame, nextRender, nextResize, nextUpdate } from '@vaadin/testing-helpers';
 
 // Utility function to assert a menu item is not visible
 const assertHidden = (elem) => {
@@ -16,26 +15,6 @@ const assertVisible = (elem) => {
   expect(style.position).to.not.equal('absolute');
 };
 
-/**
- * Resolves once the function is invoked on the given object.
- */
-function onceInvoked(object, functionName) {
-  return new Promise((resolve) => {
-    sinon.replace(object, functionName, (...args) => {
-      sinon.restore();
-      object[functionName](...args);
-      resolve();
-    });
-  });
-}
-
-/**
- * Resolves once the ResizeObserver has processed a resize.
- */
-async function onceResized(menu) {
-  await onceInvoked(menu, '__setOverflowItems');
-}
-
 describe('overflow', () => {
   describe('overflow button', () => {
     let wrapper, menu, buttons, overflow;
@@ -86,7 +65,7 @@ describe('overflow', () => {
 
     it('should show buttons and update overflow items when width increased', async () => {
       menu.style.width = '350px';
-      await onceResized(menu);
+      await nextResize(menu);
       assertVisible(buttons[2]);
       expect(buttons[2].disabled).to.not.be.true;
       assertVisible(buttons[3]);
@@ -98,7 +77,7 @@ describe('overflow', () => {
     it('should show buttons and update overflow items when width increased in RTL', async () => {
       menu.setAttribute('dir', 'rtl');
       menu.style.width = '350px';
-      await onceResized(menu);
+      await nextResize(menu);
       assertVisible(buttons[2]);
       expect(buttons[2].disabled).to.not.be.true;
       assertVisible(buttons[3]);
@@ -109,7 +88,7 @@ describe('overflow', () => {
 
     it('should hide buttons and update overflow items when width decreased', async () => {
       menu.style.width = '150px';
-      await onceResized(menu);
+      await nextResize(menu);
       assertHidden(buttons[1]);
       expect(buttons[1].disabled).to.be.true;
       expect(overflow.item.children.length).to.equal(4);
@@ -122,7 +101,7 @@ describe('overflow', () => {
     it('should hide buttons and update overflow items when width decreased in RTL', async () => {
       menu.setAttribute('dir', 'rtl');
       menu.style.width = '150px';
-      await onceResized(menu);
+      await nextResize(menu);
       assertHidden(buttons[1]);
       expect(buttons[1].disabled).to.be.true;
       expect(overflow.item.children.length).to.equal(4);
@@ -134,7 +113,7 @@ describe('overflow', () => {
 
     it('should hide overflow button and reset its items when all buttons fit', async () => {
       menu.style.width = 'auto';
-      await onceResized(menu);
+      await nextResize(menu);
       assertVisible(buttons[2]);
       expect(buttons[2].disabled).to.not.be.true;
       assertVisible(buttons[3]);
@@ -159,7 +138,7 @@ describe('overflow', () => {
 
     it('should show overflow button when theme makes buttons do not fit', async () => {
       menu.style.width = '400px';
-      await onceResized(menu);
+      await nextResize(menu);
       expect(overflow.hasAttribute('hidden')).to.be.true;
       menu.setAttribute('theme', 'big');
       await nextUpdate(menu);
@@ -176,7 +155,7 @@ describe('overflow', () => {
       expect(buttons[1].getAttribute('tabindex')).to.equal('0');
 
       menu.style.width = '150px';
-      await onceResized(menu);
+      await nextResize(menu);
 
       expect(buttons[0].getAttribute('tabindex')).to.equal('0');
       expect(buttons[1].getAttribute('tabindex')).to.equal('-1');
@@ -191,7 +170,7 @@ describe('overflow', () => {
       expect(buttons[1].getAttribute('tabindex')).to.equal('0');
 
       menu.style.width = '150px';
-      await onceResized(menu);
+      await nextResize(menu);
 
       expect(buttons[0].getAttribute('tabindex')).to.equal('0');
       expect(buttons[1].getAttribute('tabindex')).to.equal('-1');
@@ -271,7 +250,7 @@ describe('overflow', () => {
 
     it('should not set when one button and overflow are only visible', async () => {
       menu.style.width = '150px';
-      await onceResized(menu);
+      await nextResize(menu);
       assertVisible(buttons[0]);
       assertHidden(buttons[1]);
       expect(overflow.hasAttribute('hidden')).to.be.false;
@@ -280,7 +259,7 @@ describe('overflow', () => {
 
     it('should set when only overflow button is visible', async () => {
       menu.style.width = '100px';
-      await onceResized(menu);
+      await nextResize(menu);
       assertHidden(buttons[0]);
       assertHidden(buttons[1]);
       expect(menu.hasAttribute('has-single-button')).to.be.true;
@@ -288,16 +267,16 @@ describe('overflow', () => {
 
     it('should remove when buttons become visible after size increases', async () => {
       menu.style.width = '100px';
-      await onceResized(menu);
+      await nextResize(menu);
 
       menu.style.width = '150px';
-      await onceResized(menu);
+      await nextResize(menu);
       expect(menu.hasAttribute('has-single-button')).to.be.false;
     });
 
     it('should set when theme attribute makes other buttons not fit', async () => {
       menu.style.width = '150px';
-      await onceResized(menu);
+      await nextResize(menu);
 
       menu.setAttribute('theme', 'big');
       await nextUpdate(menu);
@@ -312,7 +291,7 @@ describe('overflow', () => {
 
     it('should not remove after changing items to not overflow', async () => {
       menu.style.width = '100px';
-      await onceResized(menu);
+      await nextResize(menu);
 
       menu.items = [{ text: 'Actions' }];
       await nextUpdate(menu);
@@ -358,14 +337,14 @@ describe('overflow', () => {
       // see https://github.com/vaadin/vaadin-menu-bar/issues/130
       menu.style.minWidth = '0';
       container.style.width = '150px';
-      await onceResized(menu);
+      await nextResize(menu);
       assertHidden(buttons[2]);
       expect(buttons[2].disabled).to.be.true;
       assertHidden(buttons[3]);
       expect(buttons[3].disabled).to.be.true;
 
       container.style.width = '400px';
-      await onceResized(menu);
+      await nextResize(menu);
       assertVisible(buttons[2]);
       expect(buttons[2].disabled).to.not.be.true;
       assertVisible(buttons[3]);
@@ -380,7 +359,7 @@ describe('overflow', () => {
       menu.disabled = true;
       await nextUpdate(menu);
       container.style.width = '150px';
-      await onceResized(menu);
+      await nextResize(menu);
       buttons.forEach((btn) => {
         expect(btn.disabled).to.be.true;
       });
@@ -402,7 +381,7 @@ describe('overflow', () => {
     describe('container', () => {
       beforeEach(async () => {
         container.append(text, menu);
-        await onceResized(menu);
+        await nextResize(menu);
         buttons = menu._buttons;
       });
 
@@ -411,7 +390,7 @@ describe('overflow', () => {
         assertHidden(buttons[3]);
 
         container.style.maxWidth = '400px';
-        await onceResized(menu);
+        await nextResize(menu);
 
         assertVisible(buttons[2]);
         assertVisible(buttons[3]);
@@ -425,7 +404,7 @@ describe('overflow', () => {
 
         other.append(text, menu);
         other.style.maxWidth = '400px';
-        await onceResized(menu);
+        await nextResize(menu);
 
         assertVisible(buttons[2]);
         assertVisible(buttons[3]);
@@ -436,7 +415,7 @@ describe('overflow', () => {
       beforeEach(async () => {
         container.attachShadow({ mode: 'open' });
         container.shadowRoot.append(text, menu);
-        await onceResized(menu);
+        await nextResize(menu);
         buttons = menu._buttons;
       });
 
@@ -445,7 +424,7 @@ describe('overflow', () => {
         assertHidden(buttons[3]);
 
         container.style.maxWidth = '400px';
-        await onceResized(menu);
+        await nextResize(menu);
 
         assertVisible(buttons[2]);
         assertVisible(buttons[3]);
@@ -479,14 +458,14 @@ describe('overflow', () => {
       subMenu = menu._subMenu;
 
       menu.style.width = '250px';
-      await onceResized(menu);
+      await nextResize(menu);
     });
 
     it('should close the overflow sub-menu on menu-bar resize', async () => {
       overflow.click();
       await nextRender(subMenu);
       menu.style.width = 'auto';
-      await onceResized(menu);
+      await nextResize(menu);
       expect(subMenu.opened).to.be.false;
     });
 
@@ -509,7 +488,7 @@ describe('overflow', () => {
       subMenu.close();
       await nextUpdate(menu);
       menu.style.width = 'auto';
-      await onceResized(menu);
+      await nextResize(menu);
       const item = buttons[2].firstChild;
       expect(item).to.equal(buttons[2].item.component);
       expect(item.getAttribute('role')).to.not.equal('menuitem');
@@ -523,7 +502,7 @@ describe('overflow', () => {
       subMenu.close();
       await nextUpdate(menu);
       menu.style.width = 'auto';
-      await onceResized(menu);
+      await nextResize(menu);
       expect(item.getAttributeNames()).to.have.members(itemAttributes);
     });
 
@@ -536,7 +515,7 @@ describe('overflow', () => {
       subMenu.close();
       await nextUpdate(menu);
       menu.style.width = 'auto';
-      await onceResized(menu);
+      await nextResize(menu);
       expect(item.classList.contains('test-class-1')).to.be.true;
     });
   });
diff --git a/packages/multi-select-combo-box/test/chips.test.js b/packages/multi-select-combo-box/test/chips.test.js
index fd297234b4..57082e7526 100644
--- a/packages/multi-select-combo-box/test/chips.test.js
+++ b/packages/multi-select-combo-box/test/chips.test.js
@@ -1,5 +1,5 @@
 import { expect } from '@vaadin/chai-plugins';
-import { fixtureSync, nextRender } from '@vaadin/testing-helpers';
+import { fixtureSync, nextRender, nextResize } from '@vaadin/testing-helpers';
 import { sendKeys } from '@web/test-runner-commands';
 import './not-animated-styles.js';
 import '../vaadin-multi-select-combo-box.js';
@@ -11,12 +11,6 @@ describe('chips', () => {
 
   const getChipContent = (chip) => chip.shadowRoot.querySelector('[part="label"]').textContent;
 
-  const nextResize = (target) => {
-    return new Promise((resolve) => {
-      new ResizeObserver(() => setTimeout(resolve)).observe(target);
-    });
-  };
-
   beforeEach(async () => {
     comboBox = fixtureSync(`<vaadin-multi-select-combo-box></vaadin-multi-select-combo-box>`);
     comboBox.items = ['apple', 'banana', 'lemon', 'orange'];
diff --git a/packages/tabs/test/tabs.common.js b/packages/tabs/test/tabs.common.js
index 457ecd9ad7..22ad556d26 100644
--- a/packages/tabs/test/tabs.common.js
+++ b/packages/tabs/test/tabs.common.js
@@ -7,30 +7,11 @@ import {
   listenOnce,
   nextFrame,
   nextRender,
+  nextResize,
   space,
 } from '@vaadin/testing-helpers';
 import sinon from 'sinon';
 
-/**
- * Resolves once the function is invoked on the given object.
- */
-function onceInvoked(object, functionName) {
-  return new Promise((resolve) => {
-    sinon.replace(object, functionName, (...args) => {
-      sinon.restore();
-      object[functionName](...args);
-      resolve();
-    });
-  });
-}
-
-/**
- * Resolves once the ResizeObserver has processed a resize.
- */
-async function onceResized(tabs) {
-  await onceInvoked(tabs, '_updateOverflow');
-}
-
 describe('tabs', () => {
   let tabs;
 
@@ -120,7 +101,7 @@ describe('tabs', () => {
             } else {
               tabs.style.height = '100px';
             }
-            await onceResized(tabs);
+            await nextResize(tabs);
             await nextFrame();
           });
 
@@ -182,7 +163,7 @@ describe('tabs', () => {
           it('should update overflow on resize', async () => {
             tabs.style.width = 'auto';
             tabs.style.height = 'auto';
-            await onceResized(tabs);
+            await nextResize(tabs);
             expect(tabs.hasAttribute('overflow')).to.be.false;
           });
 
@@ -193,7 +174,7 @@ describe('tabs', () => {
               item.style.minHeight = '1px';
               item.style.minWidth = '1px';
             });
-            await onceResized(tabs);
+            await nextResize(tabs);
             expect(tabs.hasAttribute('overflow')).to.be.false;
           });
 
diff --git a/packages/text-area/test/text-area.common.js b/packages/text-area/test/text-area.common.js
index f401006ae2..6848838c46 100644
--- a/packages/text-area/test/text-area.common.js
+++ b/packages/text-area/test/text-area.common.js
@@ -1,27 +1,7 @@
 import { expect } from '@vaadin/chai-plugins';
-import { fire, fixtureSync, nextFrame, nextRender, nextUpdate, oneEvent } from '@vaadin/testing-helpers';
+import { fire, fixtureSync, nextFrame, nextRender, nextResize, nextUpdate, oneEvent } from '@vaadin/testing-helpers';
 import sinon from 'sinon';
 
-/**
- * Resolves once the function is invoked on the given object.
- */
-function onceInvoked(object, functionName) {
-  return new Promise((resolve) => {
-    sinon.replace(object, functionName, (...args) => {
-      sinon.restore();
-      object[functionName](...args);
-      resolve();
-    });
-  });
-}
-
-/**
- * Resolves once the ResizeObserver has processed a resize.
- */
-async function onceResized(element) {
-  await onceInvoked(element, '_onResize');
-}
-
 describe('text-area', () => {
   let textArea;
 
@@ -303,7 +283,7 @@ describe('text-area', () => {
 
       // Decrease the width
       textArea.style.width = '400px';
-      await onceResized(textArea);
+      await nextResize(textArea);
 
       // Expect the height to have increased
       expect(textArea.offsetHeight).to.be.above(height);