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diff --git a/js/tests/unit/util/scrollbar.spec.js b/js/tests/unit/util/scrollbar.spec.js
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+++ b/js/tests/unit/util/scrollbar.spec.js
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+import * as Scrollbar from '../../../src/util/scrollbar'
+import { clearBodyAndDocument, clearFixture, getFixture } from '../../helpers/fixture'
+import Manipulator from '../../../src/dom/manipulator'
+
+describe('ScrollBar', () => {
+  let fixtureEl
+  const parseInt = arg => Number.parseInt(arg, 10)
+  const getRightPadding = el => parseInt(window.getComputedStyle(el).paddingRight)
+  const getOverFlow = el => el.style.overflow
+  const getPaddingAttr = el => Manipulator.getDataAttribute(el, 'padding-right')
+  const getOverFlowAttr = el => Manipulator.getDataAttribute(el, 'overflow')
+  const windowCalculations = () => {
+    return {
+      htmlClient: document.documentElement.clientWidth,
+      htmlOffset: document.documentElement.offsetWidth,
+      docClient: document.body.clientWidth,
+      htmlBound: document.documentElement.getBoundingClientRect().width,
+      bodyBound: document.body.getBoundingClientRect().width,
+      window: window.innerWidth,
+      width: Math.abs(window.innerWidth - document.documentElement.clientWidth)
+    }
+  }
+
+  const isScrollBarHidden = () => { // IOS devices, Android devices and Browsers on Mac, hide scrollbar by default and appear it, only while scrolling. So the tests for scrollbar would fail
+    const calc = windowCalculations()
+    return calc.htmlClient === calc.htmlOffset && calc.htmlClient === calc.window
+  }
+
+  beforeAll(() => {
+    fixtureEl = getFixture()
+    // custom fixture to avoid extreme style values
+    fixtureEl.removeAttribute('style')
+  })
+
+  afterAll(() => {
+    fixtureEl.remove()
+  })
+
+  afterEach(() => {
+    clearFixture()
+    clearBodyAndDocument()
+  })
+
+  beforeEach(() => {
+    clearBodyAndDocument()
+  })
+
+  describe('isBodyOverflowing', () => {
+    it('should return true if body is overflowing', () => {
+      document.documentElement.style.overflowY = 'scroll'
+      document.body.style.overflowY = 'scroll'
+      fixtureEl.innerHTML = [
+        '<div style="height: 110vh; width: 100%"></div>'
+      ].join('')
+      const result = Scrollbar.isBodyOverflowing()
+
+      if (isScrollBarHidden()) {
+        expect(result).toEqual(false)
+      } else {
+        expect(result).toEqual(true)
+      }
+    })
+
+    it('should return false if body is overflowing', () => {
+      document.documentElement.style.overflowY = 'hidden'
+      document.body.style.overflowY = 'hidden'
+      fixtureEl.innerHTML = [
+        '<div style="height: 110vh; width: 100%"></div>'
+      ].join('')
+      const result = Scrollbar.isBodyOverflowing()
+
+      expect(result).toEqual(false)
+    })
+  })
+
+  describe('getWidth', () => {
+    it('should return an integer greater than zero, if body is overflowing', () => {
+      document.documentElement.style.overflowY = 'scroll'
+      document.body.style.overflowY = 'scroll'
+      fixtureEl.innerHTML = [
+        '<div style="height: 110vh; width: 100%"></div>'
+      ].join('')
+      const result = Scrollbar.getWidth()
+
+      if (isScrollBarHidden()) {
+        expect(result).toBe(0)
+      } else {
+        expect(result).toBeGreaterThan(1)
+      }
+    })
+
+    it('should return 0 if body is not overflowing', () => {
+      document.documentElement.style.overflowY = 'hidden'
+      document.body.style.overflowY = 'hidden'
+      fixtureEl.innerHTML = [
+        '<div style="height: 110vh; width: 100%"></div>'
+      ].join('')
+
+      const result = Scrollbar.getWidth()
+
+      expect(result).toEqual(0)
+    })
+  })
+
+  describe('hide - reset', () => {
+    it('should adjust the inline padding of fixed elements which are full-width', done => {
+      fixtureEl.innerHTML = [
+        '<div style="height: 110vh; width: 100%">' +
+        '<div class="fixed-top" id="fixed1" style="padding-right: 0px; width: 100vw"></div>',
+        '<div class="fixed-top" id="fixed2" style="padding-right: 5px; width: 100vw"></div>',
+        '</div>'
+      ].join('')
+      document.documentElement.style.overflowY = 'scroll'
+
+      const fixedEl = fixtureEl.querySelector('#fixed1')
+      const fixedEl2 = fixtureEl.querySelector('#fixed2')
+      const originalPadding = Number.parseInt(window.getComputedStyle(fixedEl).paddingRight, 10)
+      const originalPadding2 = Number.parseInt(window.getComputedStyle(fixedEl2).paddingRight, 10)
+      const expectedPadding = originalPadding + Scrollbar.getWidth()
+      const expectedPadding2 = originalPadding2 + Scrollbar.getWidth()
+
+      Scrollbar.hide()
+
+      let currentPadding = Number.parseInt(window.getComputedStyle(fixedEl).paddingRight, 10)
+      let currentPadding2 = Number.parseInt(window.getComputedStyle(fixedEl2).paddingRight, 10)
+      expect(fixedEl.getAttribute('data-bs-padding-right')).toEqual('0px', 'original fixed element padding should be stored in data-bs-padding-right')
+      expect(fixedEl2.getAttribute('data-bs-padding-right')).toEqual('5px', 'original fixed element padding should be stored in data-bs-padding-right')
+      expect(currentPadding).toEqual(expectedPadding, 'fixed element padding should be adjusted while opening')
+      expect(currentPadding2).toEqual(expectedPadding2, 'fixed element padding should be adjusted while opening')
+
+      Scrollbar.reset()
+      currentPadding = Number.parseInt(window.getComputedStyle(fixedEl).paddingRight, 10)
+      currentPadding2 = Number.parseInt(window.getComputedStyle(fixedEl2).paddingRight, 10)
+      expect(fixedEl.getAttribute('data-bs-padding-right')).toEqual(null, 'data-bs-padding-right should be cleared after closing')
+      expect(fixedEl2.getAttribute('data-bs-padding-right')).toEqual(null, 'data-bs-padding-right should be cleared after closing')
+      expect(currentPadding).toEqual(originalPadding, 'fixed element padding should be reset after closing')
+      expect(currentPadding2).toEqual(originalPadding2, 'fixed element padding should be reset after closing')
+      done()
+    })
+
+    it('should adjust the inline margin of sticky elements', done => {
+      fixtureEl.innerHTML = [
+        '<div style="height: 110vh">' +
+        '<div class="sticky-top" style="margin-right: 0px; width: 100vw; height: 10px"></div>',
+        '</div>'
+      ].join('')
+      document.documentElement.style.overflowY = 'scroll'
+
+      const stickyTopEl = fixtureEl.querySelector('.sticky-top')
+      const originalMargin = Number.parseInt(window.getComputedStyle(stickyTopEl).marginRight, 10)
+      const expectedMargin = originalMargin - Scrollbar.getWidth()
+      Scrollbar.hide()
+
+      let currentMargin = Number.parseInt(window.getComputedStyle(stickyTopEl).marginRight, 10)
+      expect(stickyTopEl.getAttribute('data-bs-margin-right')).toEqual('0px', 'original sticky element margin should be stored in data-bs-margin-right')
+      expect(currentMargin).toEqual(expectedMargin, 'sticky element margin should be adjusted while opening')
+
+      Scrollbar.reset()
+      currentMargin = Number.parseInt(window.getComputedStyle(stickyTopEl).marginRight, 10)
+
+      expect(stickyTopEl.getAttribute('data-bs-margin-right')).toEqual(null, 'data-bs-margin-right should be cleared after closing')
+      expect(currentMargin).toEqual(originalMargin, 'sticky element margin should be reset after closing')
+      done()
+    })
+
+    it('should not adjust the inline margin and padding of sticky and fixed elements when element do not have full width', () => {
+      fixtureEl.innerHTML = [
+        '<div class="sticky-top" style="margin-right: 0px; padding-right: 0px; width: 50vw"></div>'
+      ].join('')
+
+      const stickyTopEl = fixtureEl.querySelector('.sticky-top')
+      const originalMargin = Number.parseInt(window.getComputedStyle(stickyTopEl).marginRight, 10)
+      const originalPadding = Number.parseInt(window.getComputedStyle(stickyTopEl).paddingRight, 10)
+
+      Scrollbar.hide()
+
+      const currentMargin = Number.parseInt(window.getComputedStyle(stickyTopEl).marginRight, 10)
+      const currentPadding = Number.parseInt(window.getComputedStyle(stickyTopEl).paddingRight, 10)
+
+      expect(currentMargin).toEqual(originalMargin, 'sticky element\'s margin should not be adjusted while opening')
+      expect(currentPadding).toEqual(originalPadding, 'sticky element\'s padding should not be adjusted while opening')
+
+      Scrollbar.reset()
+    })
+
+    describe('Body Handling', () => {
+      it('should hide scrollbar and reset it to its initial value', () => {
+        const styleSheetPadding = '7px'
+        fixtureEl.innerHTML = [
+          '<style>',
+          '  body {',
+          `       padding-right: ${styleSheetPadding} }`,
+          '  }',
+          '</style>'
+        ].join('')
+
+        const el = document.body
+        const inlineStylePadding = '10px'
+        el.style.paddingRight = inlineStylePadding
+
+        const originalPadding = getRightPadding(el)
+        expect(originalPadding).toEqual(parseInt(inlineStylePadding)) // Respect only the inline style as it has prevails this of css
+        const originalOverFlow = 'auto'
+        el.style.overflow = originalOverFlow
+        const scrollBarWidth = Scrollbar.getWidth()
+
+        Scrollbar.hide()
+
+        const currentPadding = getRightPadding(el)
+
+        expect(currentPadding).toEqual(scrollBarWidth + originalPadding)
+        expect(currentPadding).toEqual(scrollBarWidth + parseInt(inlineStylePadding))
+        expect(getPaddingAttr(el)).toEqual(inlineStylePadding)
+        expect(getOverFlow(el)).toEqual('hidden')
+        expect(getOverFlowAttr(el)).toEqual(originalOverFlow)
+
+        Scrollbar.reset()
+
+        const currentPadding1 = getRightPadding(el)
+        expect(currentPadding1).toEqual(originalPadding)
+        expect(getPaddingAttr(el)).toEqual(null)
+        expect(getOverFlow(el)).toEqual(originalOverFlow)
+        expect(getOverFlowAttr(el)).toEqual(null)
+      })
+
+      it('should hide scrollbar and reset it to its initial value - respecting css rules', () => {
+        const styleSheetPadding = '7px'
+        fixtureEl.innerHTML = [
+          '<style>',
+          '  body {',
+          `       padding-right: ${styleSheetPadding} }`,
+          '  }',
+          '</style>'
+        ].join('')
+        const el = document.body
+        const originalPadding = getRightPadding(el)
+        const originalOverFlow = 'scroll'
+        el.style.overflow = originalOverFlow
+        const scrollBarWidth = Scrollbar.getWidth()
+
+        Scrollbar.hide()
+
+        const currentPadding = getRightPadding(el)
+
+        expect(currentPadding).toEqual(scrollBarWidth + originalPadding)
+        expect(currentPadding).toEqual(scrollBarWidth + parseInt(styleSheetPadding))
+        expect(getPaddingAttr(el)).toBeNull() // We do not have to keep css padding
+        expect(getOverFlow(el)).toEqual('hidden')
+        expect(getOverFlowAttr(el)).toEqual(originalOverFlow)
+
+        Scrollbar.reset()
+
+        const currentPadding1 = getRightPadding(el)
+        expect(currentPadding1).toEqual(originalPadding)
+        expect(getPaddingAttr(el)).toEqual(null)
+        expect(getOverFlow(el)).toEqual(originalOverFlow)
+        expect(getOverFlowAttr(el)).toEqual(null)
+      })
+    })
+  })
+})