diff --git a/js/index.esm.js b/js/index.esm.js
index f0569d701..51a9ff8ea 100644
--- a/js/index.esm.js
+++ b/js/index.esm.js
@@ -5,15 +5,15 @@
  * --------------------------------------------------------------------------
  */
 
-export { default as Alert } from './src/alert.js'
-export { default as Button } from './src/button.js'
-export { default as Carousel } from './src/carousel.js'
-export { default as Collapse } from './src/collapse.js'
-export { default as Dropdown } from './src/dropdown.js'
-export { default as Modal } from './src/modal.js'
-export { default as Offcanvas } from './src/offcanvas.js'
-export { default as Popover } from './src/popover.js'
-export { default as ScrollSpy } from './src/scrollspy.js'
-export { default as Tab } from './src/tab.js'
-export { default as Toast } from './src/toast.js'
-export { default as Tooltip } from './src/tooltip.js'
+export { default as Alert } from './src/alert'
+export { default as Button } from './src/button'
+export { default as Carousel } from './src/carousel'
+export { default as Collapse } from './src/collapse'
+export { default as Dropdown } from './src/dropdown'
+export { default as Modal } from './src/modal'
+export { default as Offcanvas } from './src/offcanvas'
+export { default as Popover } from './src/popover'
+export { default as ScrollSpy } from './src/scrollspy'
+export { default as Tab } from './src/tab'
+export { default as Toast } from './src/toast'
+export { default as Tooltip } from './src/tooltip'
diff --git a/js/index.umd.js b/js/index.umd.js
index fc5308389..4d15d6d64 100644
--- a/js/index.umd.js
+++ b/js/index.umd.js
@@ -5,18 +5,18 @@
  * --------------------------------------------------------------------------
  */
 
-import Alert from './src/alert.js'
-import Button from './src/button.js'
-import Carousel from './src/carousel.js'
-import Collapse from './src/collapse.js'
-import Dropdown from './src/dropdown.js'
-import Modal from './src/modal.js'
-import Offcanvas from './src/offcanvas.js'
-import Popover from './src/popover.js'
-import ScrollSpy from './src/scrollspy.js'
-import Tab from './src/tab.js'
-import Toast from './src/toast.js'
-import Tooltip from './src/tooltip.js'
+import Alert from './src/alert'
+import Button from './src/button'
+import Carousel from './src/carousel'
+import Collapse from './src/collapse'
+import Dropdown from './src/dropdown'
+import Modal from './src/modal'
+import Offcanvas from './src/offcanvas'
+import Popover from './src/popover'
+import ScrollSpy from './src/scrollspy'
+import Tab from './src/tab'
+import Toast from './src/toast'
+import Tooltip from './src/tooltip'
 
 // eslint-disable-next-line import/no-anonymous-default-export
 export default {
diff --git a/js/src/alert.js b/js/src/alert.js
index af3635980..7d4b555ea 100644
--- a/js/src/alert.js
+++ b/js/src/alert.js
@@ -5,10 +5,10 @@
  * --------------------------------------------------------------------------
  */
 
-import { defineJQueryPlugin } from './util/index.js'
-import EventHandler from './dom/event-handler.js'
-import BaseComponent from './base-component.js'
-import { enableDismissTrigger } from './util/component-functions.js'
+import { defineJQueryPlugin } from './util/index'
+import EventHandler from './dom/event-handler'
+import BaseComponent from './base-component'
+import { enableDismissTrigger } from './util/component-functions'
 
 /**
  * Constants
diff --git a/js/src/base-component.js b/js/src/base-component.js
index 88e5f23c4..3c5eb460a 100644
--- a/js/src/base-component.js
+++ b/js/src/base-component.js
@@ -5,12 +5,12 @@
  * --------------------------------------------------------------------------
  */
 
-import Data from './dom/data.js'
+import Data from './dom/data'
 import {
   executeAfterTransition,
   getElement
-} from './util/index.js'
-import EventHandler from './dom/event-handler.js'
+} from './util/index'
+import EventHandler from './dom/event-handler'
 
 /**
  * Constants
diff --git a/js/src/button.js b/js/src/button.js
index 3a75a965c..e2a52e7eb 100644
--- a/js/src/button.js
+++ b/js/src/button.js
@@ -5,9 +5,9 @@
  * --------------------------------------------------------------------------
  */
 
-import { defineJQueryPlugin } from './util/index.js'
-import EventHandler from './dom/event-handler.js'
-import BaseComponent from './base-component.js'
+import { defineJQueryPlugin } from './util/index'
+import EventHandler from './dom/event-handler'
+import BaseComponent from './base-component'
 
 /**
  * Constants
diff --git a/js/src/carousel.js b/js/src/carousel.js
index aa73a4f9e..3589f2206 100644
--- a/js/src/carousel.js
+++ b/js/src/carousel.js
@@ -14,12 +14,12 @@ import {
   reflow,
   triggerTransitionEnd,
   typeCheckConfig
-} from './util/index.js'
-import EventHandler from './dom/event-handler.js'
-import Manipulator from './dom/manipulator.js'
-import SelectorEngine from './dom/selector-engine.js'
-import Swipe from './util/swipe.js'
-import BaseComponent from './base-component.js'
+} from './util/index'
+import EventHandler from './dom/event-handler'
+import Manipulator from './dom/manipulator'
+import SelectorEngine from './dom/selector-engine'
+import Swipe from './util/swipe'
+import BaseComponent from './base-component'
 
 /**
  * Constants
diff --git a/js/src/collapse.js b/js/src/collapse.js
index 4dac27a67..642f7e840 100644
--- a/js/src/collapse.js
+++ b/js/src/collapse.js
@@ -12,11 +12,11 @@ import {
   getSelectorFromElement,
   reflow,
   typeCheckConfig
-} from './util/index.js'
-import EventHandler from './dom/event-handler.js'
-import Manipulator from './dom/manipulator.js'
-import SelectorEngine from './dom/selector-engine.js'
-import BaseComponent from './base-component.js'
+} from './util/index'
+import EventHandler from './dom/event-handler'
+import Manipulator from './dom/manipulator'
+import SelectorEngine from './dom/selector-engine'
+import BaseComponent from './base-component'
 
 /**
  * Constants
diff --git a/js/src/dom/event-handler.js b/js/src/dom/event-handler.js
index 6f8f69416..b9ebce324 100644
--- a/js/src/dom/event-handler.js
+++ b/js/src/dom/event-handler.js
@@ -5,7 +5,7 @@
  * --------------------------------------------------------------------------
  */
 
-import { getjQuery } from '../util/index.js'
+import { getjQuery } from '../util/index'
 
 /**
  * Constants
diff --git a/js/src/dom/selector-engine.js b/js/src/dom/selector-engine.js
index d467ea3d9..af27dc379 100644
--- a/js/src/dom/selector-engine.js
+++ b/js/src/dom/selector-engine.js
@@ -5,7 +5,7 @@
  * --------------------------------------------------------------------------
  */
 
-import { isDisabled, isVisible } from '../util/index.js'
+import { isDisabled, isVisible } from '../util/index'
 
 /**
  * Constants
diff --git a/js/src/dropdown.js b/js/src/dropdown.js
index 40bcd9712..6129707e2 100644
--- a/js/src/dropdown.js
+++ b/js/src/dropdown.js
@@ -17,11 +17,11 @@ import {
   isVisible,
   noop,
   typeCheckConfig
-} from './util/index.js'
-import EventHandler from './dom/event-handler.js'
-import Manipulator from './dom/manipulator.js'
-import SelectorEngine from './dom/selector-engine.js'
-import BaseComponent from './base-component.js'
+} from './util/index'
+import EventHandler from './dom/event-handler'
+import Manipulator from './dom/manipulator'
+import SelectorEngine from './dom/selector-engine'
+import BaseComponent from './base-component'
 
 /**
  * Constants
diff --git a/js/src/modal.js b/js/src/modal.js
index b3402fb73..b8b144774 100644
--- a/js/src/modal.js
+++ b/js/src/modal.js
@@ -12,15 +12,15 @@ import {
   isVisible,
   reflow,
   typeCheckConfig
-} from './util/index.js'
-import EventHandler from './dom/event-handler.js'
-import Manipulator from './dom/manipulator.js'
-import SelectorEngine from './dom/selector-engine.js'
-import ScrollBarHelper from './util/scrollbar.js'
-import BaseComponent from './base-component.js'
-import Backdrop from './util/backdrop.js'
-import FocusTrap from './util/focustrap.js'
-import { enableDismissTrigger } from './util/component-functions.js'
+} from './util/index'
+import EventHandler from './dom/event-handler'
+import Manipulator from './dom/manipulator'
+import SelectorEngine from './dom/selector-engine'
+import ScrollBarHelper from './util/scrollbar'
+import BaseComponent from './base-component'
+import Backdrop from './util/backdrop'
+import FocusTrap from './util/focustrap'
+import { enableDismissTrigger } from './util/component-functions'
 
 /**
  * Constants
diff --git a/js/src/offcanvas.js b/js/src/offcanvas.js
index 8734ced97..6878b1f62 100644
--- a/js/src/offcanvas.js
+++ b/js/src/offcanvas.js
@@ -11,15 +11,15 @@ import {
   isDisabled,
   isVisible,
   typeCheckConfig
-} from './util/index.js'
-import ScrollBarHelper from './util/scrollbar.js'
-import EventHandler from './dom/event-handler.js'
-import BaseComponent from './base-component.js'
-import SelectorEngine from './dom/selector-engine.js'
-import Manipulator from './dom/manipulator.js'
-import Backdrop from './util/backdrop.js'
-import FocusTrap from './util/focustrap.js'
-import { enableDismissTrigger } from './util/component-functions.js'
+} from './util/index'
+import ScrollBarHelper from './util/scrollbar'
+import EventHandler from './dom/event-handler'
+import BaseComponent from './base-component'
+import SelectorEngine from './dom/selector-engine'
+import Manipulator from './dom/manipulator'
+import Backdrop from './util/backdrop'
+import FocusTrap from './util/focustrap'
+import { enableDismissTrigger } from './util/component-functions'
 
 /**
  * Constants
diff --git a/js/src/popover.js b/js/src/popover.js
index f4b47b87d..19c1e42a4 100644
--- a/js/src/popover.js
+++ b/js/src/popover.js
@@ -5,8 +5,8 @@
  * --------------------------------------------------------------------------
  */
 
-import { defineJQueryPlugin } from './util/index.js'
-import Tooltip from './tooltip.js'
+import { defineJQueryPlugin } from './util/index'
+import Tooltip from './tooltip'
 
 /**
  * Constants
diff --git a/js/src/scrollspy.js b/js/src/scrollspy.js
index 32630b1c7..e2fa76c7f 100644
--- a/js/src/scrollspy.js
+++ b/js/src/scrollspy.js
@@ -10,11 +10,11 @@ import {
   getElement,
   getSelectorFromElement,
   typeCheckConfig
-} from './util/index.js'
-import EventHandler from './dom/event-handler.js'
-import Manipulator from './dom/manipulator.js'
-import SelectorEngine from './dom/selector-engine.js'
-import BaseComponent from './base-component.js'
+} from './util/index'
+import EventHandler from './dom/event-handler'
+import Manipulator from './dom/manipulator'
+import SelectorEngine from './dom/selector-engine'
+import BaseComponent from './base-component'
 
 /**
  * Constants
diff --git a/js/src/tab.js b/js/src/tab.js
index d4ccf9987..4a018ca77 100644
--- a/js/src/tab.js
+++ b/js/src/tab.js
@@ -10,10 +10,10 @@ import {
   getElementFromSelector,
   isDisabled,
   reflow
-} from './util/index.js'
-import EventHandler from './dom/event-handler.js'
-import SelectorEngine from './dom/selector-engine.js'
-import BaseComponent from './base-component.js'
+} from './util/index'
+import EventHandler from './dom/event-handler'
+import SelectorEngine from './dom/selector-engine'
+import BaseComponent from './base-component'
 
 /**
  * Constants
diff --git a/js/src/toast.js b/js/src/toast.js
index a4f216a20..c45721c8f 100644
--- a/js/src/toast.js
+++ b/js/src/toast.js
@@ -9,11 +9,11 @@ import {
   defineJQueryPlugin,
   reflow,
   typeCheckConfig
-} from './util/index.js'
-import EventHandler from './dom/event-handler.js'
-import Manipulator from './dom/manipulator.js'
-import BaseComponent from './base-component.js'
-import { enableDismissTrigger } from './util/component-functions.js'
+} from './util/index'
+import EventHandler from './dom/event-handler'
+import Manipulator from './dom/manipulator'
+import BaseComponent from './base-component'
+import { enableDismissTrigger } from './util/component-functions'
 
 /**
  * Constants
diff --git a/js/src/tooltip.js b/js/src/tooltip.js
index bd80672d8..b09ab0d0c 100644
--- a/js/src/tooltip.js
+++ b/js/src/tooltip.js
@@ -14,13 +14,13 @@ import {
   isRTL,
   noop,
   typeCheckConfig
-} from './util/index.js'
-import { DefaultAllowlist } from './util/sanitizer.js'
-import Data from './dom/data.js'
-import EventHandler from './dom/event-handler.js'
-import Manipulator from './dom/manipulator.js'
-import BaseComponent from './base-component.js'
-import TemplateFactory from './util/template-factory.js'
+} from './util/index'
+import { DefaultAllowlist } from './util/sanitizer'
+import Data from './dom/data'
+import EventHandler from './dom/event-handler'
+import Manipulator from './dom/manipulator'
+import BaseComponent from './base-component'
+import TemplateFactory from './util/template-factory'
 
 /**
  * Constants
diff --git a/js/src/util/backdrop.js b/js/src/util/backdrop.js
index 7fd3cd0e9..fb1b2776b 100644
--- a/js/src/util/backdrop.js
+++ b/js/src/util/backdrop.js
@@ -5,8 +5,8 @@
  * --------------------------------------------------------------------------
  */
 
-import EventHandler from '../dom/event-handler.js'
-import { execute, executeAfterTransition, getElement, reflow, typeCheckConfig } from './index.js'
+import EventHandler from '../dom/event-handler'
+import { execute, executeAfterTransition, getElement, reflow, typeCheckConfig } from './index'
 
 /**
  * Constants
diff --git a/js/src/util/component-functions.js b/js/src/util/component-functions.js
index b383e5205..bd44c3fdc 100644
--- a/js/src/util/component-functions.js
+++ b/js/src/util/component-functions.js
@@ -5,8 +5,8 @@
  * --------------------------------------------------------------------------
  */
 
-import EventHandler from '../dom/event-handler.js'
-import { getElementFromSelector, isDisabled } from './index.js'
+import EventHandler from '../dom/event-handler'
+import { getElementFromSelector, isDisabled } from './index'
 
 const enableDismissTrigger = (component, method = 'hide') => {
   const clickEvent = `click.dismiss${component.EVENT_KEY}`
diff --git a/js/src/util/focustrap.js b/js/src/util/focustrap.js
index 2ee381472..a1975f489 100644
--- a/js/src/util/focustrap.js
+++ b/js/src/util/focustrap.js
@@ -5,9 +5,9 @@
  * --------------------------------------------------------------------------
  */
 
-import EventHandler from '../dom/event-handler.js'
-import SelectorEngine from '../dom/selector-engine.js'
-import { typeCheckConfig } from './index.js'
+import EventHandler from '../dom/event-handler'
+import SelectorEngine from '../dom/selector-engine'
+import { typeCheckConfig } from './index'
 
 /**
  * Constants
diff --git a/js/src/util/scrollbar.js b/js/src/util/scrollbar.js
index 2ca65fe31..55b7244ab 100644
--- a/js/src/util/scrollbar.js
+++ b/js/src/util/scrollbar.js
@@ -5,9 +5,9 @@
  * --------------------------------------------------------------------------
  */
 
-import SelectorEngine from '../dom/selector-engine.js'
-import Manipulator from '../dom/manipulator.js'
-import { isElement } from './index.js'
+import SelectorEngine from '../dom/selector-engine'
+import Manipulator from '../dom/manipulator'
+import { isElement } from './index'
 
 /**
  * Constants
diff --git a/js/src/util/swipe.js b/js/src/util/swipe.js
index 4baf00a1c..87a5f7f5a 100644
--- a/js/src/util/swipe.js
+++ b/js/src/util/swipe.js
@@ -5,8 +5,8 @@
  * --------------------------------------------------------------------------
  */
 
-import EventHandler from '../dom/event-handler.js'
-import { execute, typeCheckConfig } from './index.js'
+import EventHandler from '../dom/event-handler'
+import { execute, typeCheckConfig } from './index'
 
 /**
  * Constants
diff --git a/js/src/util/template-factory.js b/js/src/util/template-factory.js
index 5e52a7309..25ceeb274 100644
--- a/js/src/util/template-factory.js
+++ b/js/src/util/template-factory.js
@@ -5,9 +5,9 @@
  * --------------------------------------------------------------------------
  */
 
-import { getElement, isElement, typeCheckConfig } from '../util/index.js'
-import SelectorEngine from '../dom/selector-engine.js'
-import { DefaultAllowlist, sanitizeHtml } from './sanitizer.js'
+import { getElement, isElement, typeCheckConfig } from '../util/index'
+import SelectorEngine from '../dom/selector-engine'
+import { DefaultAllowlist, sanitizeHtml } from './sanitizer'
 
 /**
  * Constants
diff --git a/js/tests/integration/bundle-modularity.js b/js/tests/integration/bundle-modularity.js
index d8f6fc0df..80761d64a 100644
--- a/js/tests/integration/bundle-modularity.js
+++ b/js/tests/integration/bundle-modularity.js
@@ -1,5 +1,5 @@
-import Tooltip from '../../dist/tooltip.js'
-import '../../dist/carousel.js' // eslint-disable-line import/no-unassigned-import
+import Tooltip from '../../dist/tooltip'
+import '../../dist/carousel' // eslint-disable-line import/no-unassigned-import
 
 window.addEventListener('load', () => {
   [].concat(...document.querySelectorAll('[data-bs-toggle="tooltip"]'))
diff --git a/js/tests/karma.conf.js b/js/tests/karma.conf.js
index e35155b38..dbf417bfb 100644
--- a/js/tests/karma.conf.js
+++ b/js/tests/karma.conf.js
@@ -9,7 +9,7 @@ const { babel } = require('@rollup/plugin-babel')
 const istanbul = require('rollup-plugin-istanbul')
 const { nodeResolve } = require('@rollup/plugin-node-resolve')
 const replace = require('@rollup/plugin-replace')
-const { browsers } = require('./browsers.js')
+const { browsers } = require('./browsers')
 
 const ENV = process.env
 const BROWSERSTACK = Boolean(ENV.BROWSERSTACK)
diff --git a/js/tests/unit/alert.spec.js b/js/tests/unit/alert.spec.js
index 184872eb9..210ae9a25 100644
--- a/js/tests/unit/alert.spec.js
+++ b/js/tests/unit/alert.spec.js
@@ -1,6 +1,6 @@
-import Alert from '../../src/alert.js'
-import { getTransitionDurationFromElement } from '../../src/util/index.js'
-import { clearFixture, getFixture, jQueryMock } from '../helpers/fixture.js'
+import Alert from '../../src/alert'
+import { getTransitionDurationFromElement } from '../../src/util/index'
+import { clearFixture, getFixture, jQueryMock } from '../helpers/fixture'
 
 describe('Alert', () => {
   let fixtureEl
diff --git a/js/tests/unit/base-component.spec.js b/js/tests/unit/base-component.spec.js
index cc1814ef1..9e0b872d4 100644
--- a/js/tests/unit/base-component.spec.js
+++ b/js/tests/unit/base-component.spec.js
@@ -1,7 +1,7 @@
-import BaseComponent from '../../src/base-component.js'
-import { clearFixture, getFixture } from '../helpers/fixture.js'
-import EventHandler from '../../src/dom/event-handler.js'
-import { noop } from '../../src/util/index.js'
+import BaseComponent from '../../src/base-component'
+import { clearFixture, getFixture } from '../helpers/fixture'
+import EventHandler from '../../src/dom/event-handler'
+import { noop } from '../../src/util'
 
 class DummyClass extends BaseComponent {
   constructor(element) {
diff --git a/js/tests/unit/button.spec.js b/js/tests/unit/button.spec.js
index a5e4a0ef3..30e62f0b3 100644
--- a/js/tests/unit/button.spec.js
+++ b/js/tests/unit/button.spec.js
@@ -1,5 +1,5 @@
-import Button from '../../src/button.js'
-import { getFixture, clearFixture, jQueryMock } from '../helpers/fixture.js'
+import Button from '../../src/button'
+import { getFixture, clearFixture, jQueryMock } from '../helpers/fixture'
 
 describe('Button', () => {
   let fixtureEl
diff --git a/js/tests/unit/carousel.spec.js b/js/tests/unit/carousel.spec.js
index 57c7cb538..66f4a8367 100644
--- a/js/tests/unit/carousel.spec.js
+++ b/js/tests/unit/carousel.spec.js
@@ -1,8 +1,8 @@
-import Carousel from '../../src/carousel.js'
-import EventHandler from '../../src/dom/event-handler.js'
-import { clearFixture, createEvent, getFixture, jQueryMock } from '../helpers/fixture.js'
-import { isRTL, noop } from '../../src/util/index.js'
-import Swipe from '../../src/util/swipe.js'
+import Carousel from '../../src/carousel'
+import EventHandler from '../../src/dom/event-handler'
+import { clearFixture, createEvent, getFixture, jQueryMock } from '../helpers/fixture'
+import { isRTL, noop } from '../../src/util/index'
+import Swipe from '../../src/util/swipe'
 
 describe('Carousel', () => {
   const { Simulator, PointerEvent } = window
diff --git a/js/tests/unit/collapse.spec.js b/js/tests/unit/collapse.spec.js
index 20e399de8..a7635006f 100644
--- a/js/tests/unit/collapse.spec.js
+++ b/js/tests/unit/collapse.spec.js
@@ -1,6 +1,6 @@
-import Collapse from '../../src/collapse.js'
-import EventHandler from '../../src/dom/event-handler.js'
-import { clearFixture, getFixture, jQueryMock } from '../helpers/fixture.js'
+import Collapse from '../../src/collapse'
+import EventHandler from '../../src/dom/event-handler'
+import { clearFixture, getFixture, jQueryMock } from '../helpers/fixture'
 
 describe('Collapse', () => {
   let fixtureEl
diff --git a/js/tests/unit/dom/data.spec.js b/js/tests/unit/dom/data.spec.js
index 7e45a076c..e898cbba2 100644
--- a/js/tests/unit/dom/data.spec.js
+++ b/js/tests/unit/dom/data.spec.js
@@ -1,5 +1,5 @@
-import Data from '../../../src/dom/data.js'
-import { getFixture, clearFixture } from '../../helpers/fixture.js'
+import Data from '../../../src/dom/data'
+import { getFixture, clearFixture } from '../../helpers/fixture'
 
 describe('Data', () => {
   const TEST_KEY = 'bs.test'
diff --git a/js/tests/unit/dom/event-handler.spec.js b/js/tests/unit/dom/event-handler.spec.js
index 942d2db96..4772d892e 100644
--- a/js/tests/unit/dom/event-handler.spec.js
+++ b/js/tests/unit/dom/event-handler.spec.js
@@ -1,5 +1,5 @@
-import EventHandler from '../../../src/dom/event-handler.js'
-import { getFixture, clearFixture } from '../../helpers/fixture.js'
+import EventHandler from '../../../src/dom/event-handler'
+import { getFixture, clearFixture } from '../../helpers/fixture'
 
 describe('EventHandler', () => {
   let fixtureEl
diff --git a/js/tests/unit/dom/manipulator.spec.js b/js/tests/unit/dom/manipulator.spec.js
index 7e292e62c..963ee5989 100644
--- a/js/tests/unit/dom/manipulator.spec.js
+++ b/js/tests/unit/dom/manipulator.spec.js
@@ -1,5 +1,5 @@
-import Manipulator from '../../../src/dom/manipulator.js'
-import { getFixture, clearFixture } from '../../helpers/fixture.js'
+import Manipulator from '../../../src/dom/manipulator'
+import { getFixture, clearFixture } from '../../helpers/fixture'
 
 describe('Manipulator', () => {
   let fixtureEl
diff --git a/js/tests/unit/dom/selector-engine.spec.js b/js/tests/unit/dom/selector-engine.spec.js
index 4206f73b3..005e92704 100644
--- a/js/tests/unit/dom/selector-engine.spec.js
+++ b/js/tests/unit/dom/selector-engine.spec.js
@@ -1,5 +1,5 @@
-import SelectorEngine from '../../../src/dom/selector-engine.js'
-import { getFixture, clearFixture } from '../../helpers/fixture.js'
+import SelectorEngine from '../../../src/dom/selector-engine'
+import { getFixture, clearFixture } from '../../helpers/fixture'
 
 describe('SelectorEngine', () => {
   let fixtureEl
diff --git a/js/tests/unit/dropdown.spec.js b/js/tests/unit/dropdown.spec.js
index bdd45b673..9c0eae6d8 100644
--- a/js/tests/unit/dropdown.spec.js
+++ b/js/tests/unit/dropdown.spec.js
@@ -1,7 +1,7 @@
-import Dropdown from '../../src/dropdown.js'
-import EventHandler from '../../src/dom/event-handler.js'
-import { noop } from '../../src/util/index.js'
-import { clearFixture, createEvent, getFixture, jQueryMock } from '../helpers/fixture.js'
+import Dropdown from '../../src/dropdown'
+import EventHandler from '../../src/dom/event-handler'
+import { noop } from '../../src/util/index'
+import { clearFixture, createEvent, getFixture, jQueryMock } from '../helpers/fixture'
 
 describe('Dropdown', () => {
   let fixtureEl
diff --git a/js/tests/unit/jquery.spec.js b/js/tests/unit/jquery.spec.js
index 0681ea463..16781a351 100644
--- a/js/tests/unit/jquery.spec.js
+++ b/js/tests/unit/jquery.spec.js
@@ -1,18 +1,18 @@
 /* eslint-env jquery */
 
-import Alert from '../../src/alert.js'
-import Button from '../../src/button.js'
-import Carousel from '../../src/carousel.js'
-import Collapse from '../../src/collapse.js'
-import Dropdown from '../../src/dropdown.js'
-import Modal from '../../src/modal.js'
-import Offcanvas from '../../src/offcanvas.js'
-import Popover from '../../src/popover.js'
-import ScrollSpy from '../../src/scrollspy.js'
-import Tab from '../../src/tab.js'
-import Toast from '../../src/toast.js'
-import Tooltip from '../../src/tooltip.js'
-import { getFixture, clearFixture } from '../helpers/fixture.js'
+import Alert from '../../src/alert'
+import Button from '../../src/button'
+import Carousel from '../../src/carousel'
+import Collapse from '../../src/collapse'
+import Dropdown from '../../src/dropdown'
+import Modal from '../../src/modal'
+import Offcanvas from '../../src/offcanvas'
+import Popover from '../../src/popover'
+import ScrollSpy from '../../src/scrollspy'
+import Tab from '../../src/tab'
+import Toast from '../../src/toast'
+import Tooltip from '../../src/tooltip'
+import { getFixture, clearFixture } from '../helpers/fixture'
 
 describe('jQuery', () => {
   let fixtureEl
diff --git a/js/tests/unit/modal.spec.js b/js/tests/unit/modal.spec.js
index ddc718373..5729942e5 100644
--- a/js/tests/unit/modal.spec.js
+++ b/js/tests/unit/modal.spec.js
@@ -1,7 +1,7 @@
-import Modal from '../../src/modal.js'
-import EventHandler from '../../src/dom/event-handler.js'
-import ScrollBarHelper from '../../src/util/scrollbar.js'
-import { clearBodyAndDocument, clearFixture, createEvent, getFixture, jQueryMock } from '../helpers/fixture.js'
+import Modal from '../../src/modal'
+import EventHandler from '../../src/dom/event-handler'
+import ScrollBarHelper from '../../src/util/scrollbar'
+import { clearBodyAndDocument, clearFixture, createEvent, getFixture, jQueryMock } from '../helpers/fixture'
 
 describe('Modal', () => {
   let fixtureEl
diff --git a/js/tests/unit/offcanvas.spec.js b/js/tests/unit/offcanvas.spec.js
index a54b74ffd..191a9f801 100644
--- a/js/tests/unit/offcanvas.spec.js
+++ b/js/tests/unit/offcanvas.spec.js
@@ -1,8 +1,8 @@
-import Offcanvas from '../../src/offcanvas.js'
-import EventHandler from '../../src/dom/event-handler.js'
-import { clearBodyAndDocument, clearFixture, createEvent, getFixture, jQueryMock } from '../helpers/fixture.js'
-import { isVisible } from '../../src/util/index.js'
-import ScrollBarHelper from '../../src/util/scrollbar.js'
+import Offcanvas from '../../src/offcanvas'
+import EventHandler from '../../src/dom/event-handler'
+import { clearBodyAndDocument, clearFixture, createEvent, getFixture, jQueryMock } from '../helpers/fixture'
+import { isVisible } from '../../src/util/index'
+import ScrollBarHelper from '../../src/util/scrollbar'
 
 describe('Offcanvas', () => {
   let fixtureEl
diff --git a/js/tests/unit/popover.spec.js b/js/tests/unit/popover.spec.js
index b844967d2..606d7370c 100644
--- a/js/tests/unit/popover.spec.js
+++ b/js/tests/unit/popover.spec.js
@@ -1,5 +1,5 @@
-import Popover from '../../src/popover.js'
-import { clearFixture, getFixture, jQueryMock } from '../helpers/fixture.js'
+import Popover from '../../src/popover'
+import { clearFixture, getFixture, jQueryMock } from '../helpers/fixture'
 
 describe('Popover', () => {
   let fixtureEl
diff --git a/js/tests/unit/scrollspy.spec.js b/js/tests/unit/scrollspy.spec.js
index ecf013054..5c044e697 100644
--- a/js/tests/unit/scrollspy.spec.js
+++ b/js/tests/unit/scrollspy.spec.js
@@ -1,6 +1,6 @@
-import ScrollSpy from '../../src/scrollspy.js'
-import Manipulator from '../../src/dom/manipulator.js'
-import { getFixture, clearFixture, createEvent, jQueryMock } from '../helpers/fixture.js'
+import ScrollSpy from '../../src/scrollspy'
+import Manipulator from '../../src/dom/manipulator'
+import { getFixture, clearFixture, createEvent, jQueryMock } from '../helpers/fixture'
 
 describe('ScrollSpy', () => {
   let fixtureEl
diff --git a/js/tests/unit/tab.spec.js b/js/tests/unit/tab.spec.js
index 56f0b4ecc..43d20438e 100644
--- a/js/tests/unit/tab.spec.js
+++ b/js/tests/unit/tab.spec.js
@@ -1,5 +1,5 @@
-import Tab from '../../src/tab.js'
-import { getFixture, clearFixture, jQueryMock } from '../helpers/fixture.js'
+import Tab from '../../src/tab'
+import { getFixture, clearFixture, jQueryMock } from '../helpers/fixture'
 
 describe('Tab', () => {
   let fixtureEl
diff --git a/js/tests/unit/toast.spec.js b/js/tests/unit/toast.spec.js
index 5712e7759..c4ea43808 100644
--- a/js/tests/unit/toast.spec.js
+++ b/js/tests/unit/toast.spec.js
@@ -1,5 +1,5 @@
-import Toast from '../../src/toast.js'
-import { getFixture, clearFixture, createEvent, jQueryMock } from '../helpers/fixture.js'
+import Toast from '../../src/toast'
+import { getFixture, clearFixture, createEvent, jQueryMock } from '../helpers/fixture'
 
 describe('Toast', () => {
   let fixtureEl
diff --git a/js/tests/unit/tooltip.spec.js b/js/tests/unit/tooltip.spec.js
index dceee8e79..d261986c3 100644
--- a/js/tests/unit/tooltip.spec.js
+++ b/js/tests/unit/tooltip.spec.js
@@ -1,7 +1,7 @@
-import Tooltip from '../../src/tooltip.js'
-import EventHandler from '../../src/dom/event-handler.js'
-import { noop } from '../../src/util/index.js'
-import { clearFixture, createEvent, getFixture, jQueryMock } from '../helpers/fixture.js'
+import Tooltip from '../../src/tooltip'
+import EventHandler from '../../src/dom/event-handler'
+import { noop } from '../../src/util/index'
+import { clearFixture, createEvent, getFixture, jQueryMock } from '../helpers/fixture'
 
 describe('Tooltip', () => {
   let fixtureEl
diff --git a/js/tests/unit/util/backdrop.spec.js b/js/tests/unit/util/backdrop.spec.js
index 805210883..430369380 100644
--- a/js/tests/unit/util/backdrop.spec.js
+++ b/js/tests/unit/util/backdrop.spec.js
@@ -1,6 +1,6 @@
-import Backdrop from '../../../src/util/backdrop.js'
-import { getTransitionDurationFromElement } from '../../../src/util/index.js'
-import { clearFixture, getFixture } from '../../helpers/fixture.js'
+import Backdrop from '../../../src/util/backdrop'
+import { getTransitionDurationFromElement } from '../../../src/util/index'
+import { clearFixture, getFixture } from '../../helpers/fixture'
 
 const CLASS_BACKDROP = '.modal-backdrop'
 const CLASS_NAME_FADE = 'fade'
diff --git a/js/tests/unit/util/component-functions.spec.js b/js/tests/unit/util/component-functions.spec.js
index 754364b40..16f910a63 100644
--- a/js/tests/unit/util/component-functions.spec.js
+++ b/js/tests/unit/util/component-functions.spec.js
@@ -1,8 +1,8 @@
 /* Test helpers */
 
-import { clearFixture, createEvent, getFixture } from '../../helpers/fixture.js'
-import { enableDismissTrigger } from '../../../src/util/component-functions.js'
-import BaseComponent from '../../../src/base-component.js'
+import { clearFixture, createEvent, getFixture } from '../../helpers/fixture'
+import { enableDismissTrigger } from '../../../src/util/component-functions'
+import BaseComponent from '../../../src/base-component'
 
 class DummyClass2 extends BaseComponent {
   static get NAME() {
diff --git a/js/tests/unit/util/focustrap.spec.js b/js/tests/unit/util/focustrap.spec.js
index 48b68560f..52a757397 100644
--- a/js/tests/unit/util/focustrap.spec.js
+++ b/js/tests/unit/util/focustrap.spec.js
@@ -1,7 +1,7 @@
-import FocusTrap from '../../../src/util/focustrap.js'
-import EventHandler from '../../../src/dom/event-handler.js'
-import SelectorEngine from '../../../src/dom/selector-engine.js'
-import { clearFixture, getFixture, createEvent } from '../../helpers/fixture.js'
+import FocusTrap from '../../../src/util/focustrap'
+import EventHandler from '../../../src/dom/event-handler'
+import SelectorEngine from '../../../src/dom/selector-engine'
+import { clearFixture, getFixture, createEvent } from '../../helpers/fixture'
 
 describe('FocusTrap', () => {
   let fixtureEl
diff --git a/js/tests/unit/util/index.spec.js b/js/tests/unit/util/index.spec.js
index ffe28cd02..a9e446c9d 100644
--- a/js/tests/unit/util/index.spec.js
+++ b/js/tests/unit/util/index.spec.js
@@ -1,5 +1,5 @@
-import * as Util from '../../../src/util/index.js'
-import { clearFixture, getFixture } from '../../helpers/fixture.js'
+import * as Util from '../../../src/util/index'
+import { clearFixture, getFixture } from '../../helpers/fixture'
 
 describe('Util', () => {
   let fixtureEl
diff --git a/js/tests/unit/util/sanitizer.spec.js b/js/tests/unit/util/sanitizer.spec.js
index 79fdc7ee4..28d624c87 100644
--- a/js/tests/unit/util/sanitizer.spec.js
+++ b/js/tests/unit/util/sanitizer.spec.js
@@ -1,4 +1,4 @@
-import { DefaultAllowlist, sanitizeHtml } from '../../../src/util/sanitizer.js'
+import { DefaultAllowlist, sanitizeHtml } from '../../../src/util/sanitizer'
 
 describe('Sanitizer', () => {
   describe('sanitizeHtml', () => {
diff --git a/js/tests/unit/util/scrollbar.spec.js b/js/tests/unit/util/scrollbar.spec.js
index 2189b54fd..15f09c0b2 100644
--- a/js/tests/unit/util/scrollbar.spec.js
+++ b/js/tests/unit/util/scrollbar.spec.js
@@ -1,6 +1,6 @@
-import { clearBodyAndDocument, clearFixture, getFixture } from '../../helpers/fixture.js'
-import Manipulator from '../../../src/dom/manipulator.js'
-import ScrollBarHelper from '../../../src/util/scrollbar.js'
+import { clearBodyAndDocument, clearFixture, getFixture } from '../../helpers/fixture'
+import Manipulator from '../../../src/dom/manipulator'
+import ScrollBarHelper from '../../../src/util/scrollbar'
 
 describe('ScrollBar', () => {
   let fixtureEl
diff --git a/js/tests/unit/util/swipe.spec.js b/js/tests/unit/util/swipe.spec.js
index 82c53a203..93131b8fd 100644
--- a/js/tests/unit/util/swipe.spec.js
+++ b/js/tests/unit/util/swipe.spec.js
@@ -1,7 +1,7 @@
-import { clearFixture, getFixture } from '../../helpers/fixture.js'
-import EventHandler from '../../../src/dom/event-handler.js'
-import Swipe from '../../../src/util/swipe.js'
-import { noop } from '../../../src/util/index.js'
+import { clearFixture, getFixture } from '../../helpers/fixture'
+import EventHandler from '../../../src/dom/event-handler'
+import Swipe from '../../../src/util/swipe'
+import { noop } from '../../../src/util'
 
 describe('Swipe', () => {
   const { Simulator, PointerEvent } = window
diff --git a/js/tests/unit/util/template-factory.spec.js b/js/tests/unit/util/template-factory.spec.js
index e0074c1c1..0fdf87146 100644
--- a/js/tests/unit/util/template-factory.spec.js
+++ b/js/tests/unit/util/template-factory.spec.js
@@ -1,5 +1,5 @@
-import { clearFixture, getFixture } from '../../helpers/fixture.js'
-import TemplateFactory from '../../../src/util/template-factory.js'
+import { clearFixture, getFixture } from '../../helpers/fixture'
+import TemplateFactory from '../../../src/util/template-factory'
 
 describe('TemplateFactory', () => {
   let fixtureEl
diff --git a/package.json b/package.json
index 585708615..630f01b95 100644
--- a/package.json
+++ b/package.json
@@ -191,6 +191,7 @@
         "error",
         "never"
       ],
+      "import/extensions": "off",
       "max-params": [
         "warn",
         5
@@ -203,6 +204,7 @@
       ],
       "no-console": "error",
       "no-negated-condition": "off",
+      "node/file-extension-in-import": "off",
       "object-curly-spacing": [
         "error",
         "always"