diff --git a/.eslintrc.js b/.eslintrc.js
index c830d463f4..84507b6f8b 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -480,8 +480,11 @@ module.exports = {
       rules: {
         'no-extra-semi': 'off',
         'no-restricted-syntax': ['error', {
-          selector: 'ImportDeclaration[importKind="type"][source.value=/^\\./]:not([source.value=/\\.js$/])',
+          selector: 'ImportDeclaration[importKind="type"][source.value=/^(\\.+|@uppy\\x2F[a-z-0-9]+)\\x2F/]:not([source.value=/^@uppy\\x2Futils\\x2F/]):not([source.value=/\\.js$/])',
           message: 'Use ".js" file extension for import type declarations',
+        }, {
+          selector: 'ImportDeclaration[source.value=/^@uppy\\x2Futils\\x2Flib\\x2F.+\\.[mc]?[jt]sx?$/]',
+          message: 'Do not use file extension when importing from @uppy/utils',
         }],
         'import/prefer-default-export': 'off',
         '@typescript-eslint/no-empty-function': 'off',
diff --git a/packages/@uppy/audio/src/Audio.tsx b/packages/@uppy/audio/src/Audio.tsx
index a41d7b9b08..c3822e9a58 100644
--- a/packages/@uppy/audio/src/Audio.tsx
+++ b/packages/@uppy/audio/src/Audio.tsx
@@ -6,7 +6,7 @@ import type {
   Meta,
   MinimalRequiredUppyFile,
 } from '@uppy/utils/lib/UppyFile'
-import type { Uppy } from '@uppy/core/lib/Uppy'
+import type { Uppy } from '@uppy/core/lib/Uppy.js'
 
 import getFileTypeExtension from '@uppy/utils/lib/getFileTypeExtension'
 import supportsMediaRecorder from './supportsMediaRecorder.ts'
diff --git a/packages/@uppy/box/src/Box.tsx b/packages/@uppy/box/src/Box.tsx
index 21b2ef7ebc..74c0e903b6 100644
--- a/packages/@uppy/box/src/Box.tsx
+++ b/packages/@uppy/box/src/Box.tsx
@@ -9,7 +9,7 @@ import { ProviderViews } from '@uppy/provider-views'
 import { h, type ComponentChild } from 'preact'
 
 import type { UppyFile, Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy'
+import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy.js'
 import locale from './locale.ts'
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
 // @ts-ignore We don't want TS to generate types for the package.json
diff --git a/packages/@uppy/companion-client/src/Provider.ts b/packages/@uppy/companion-client/src/Provider.ts
index 2c9bc7b938..2f76eae70e 100644
--- a/packages/@uppy/companion-client/src/Provider.ts
+++ b/packages/@uppy/companion-client/src/Provider.ts
@@ -1,11 +1,11 @@
 import type { Uppy } from '@uppy/core'
 import type { Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { PluginOpts } from '@uppy/core/lib/BasePlugin'
+import type { PluginOpts } from '@uppy/core/lib/BasePlugin.js'
 import type {
   RequestOptions,
   CompanionClientProvider,
 } from '@uppy/utils/lib/CompanionClientProvider'
-import type { UnknownProviderPlugin } from '@uppy/core/lib/Uppy'
+import type { UnknownProviderPlugin } from '@uppy/core/lib/Uppy.js'
 import RequestClient, { authErrorStatusCode } from './RequestClient.ts'
 import type { CompanionPluginOptions } from './index.js'
 
diff --git a/packages/@uppy/compressor/src/index.ts b/packages/@uppy/compressor/src/index.ts
index 4a46fad7b2..ba55378f5b 100644
--- a/packages/@uppy/compressor/src/index.ts
+++ b/packages/@uppy/compressor/src/index.ts
@@ -7,7 +7,7 @@ import prettierBytes from '@transloadit/prettier-bytes'
 import CompressorJS from 'compressorjs'
 
 import type { Body, Meta, UppyFile } from '@uppy/utils/lib/UppyFile'
-import type { PluginOpts } from '@uppy/core/lib/BasePlugin'
+import type { PluginOpts } from '@uppy/core/lib/BasePlugin.js'
 
 import locale from './locale.ts'
 
diff --git a/packages/@uppy/dashboard/src/Dashboard.tsx b/packages/@uppy/dashboard/src/Dashboard.tsx
index 3aa6f07352..42cf5efce2 100644
--- a/packages/@uppy/dashboard/src/Dashboard.tsx
+++ b/packages/@uppy/dashboard/src/Dashboard.tsx
@@ -7,7 +7,7 @@ import {
   type State,
 } from '@uppy/core'
 import type { ComponentChild, VNode } from 'preact'
-import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin'
+import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin.js'
 import type { Body, Meta, UppyFile } from '@uppy/utils/lib/UppyFile'
 import StatusBar from '@uppy/status-bar'
 import Informer from '@uppy/informer'
diff --git a/packages/@uppy/drag-drop/src/DragDrop.tsx b/packages/@uppy/drag-drop/src/DragDrop.tsx
index cafbc3232d..27a8ab771a 100644
--- a/packages/@uppy/drag-drop/src/DragDrop.tsx
+++ b/packages/@uppy/drag-drop/src/DragDrop.tsx
@@ -1,6 +1,6 @@
 import { UIPlugin, type Uppy } from '@uppy/core'
-import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin'
-import type { UIPluginOptions } from '@uppy/core/lib/UIPlugin'
+import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin.js'
+import type { UIPluginOptions } from '@uppy/core/lib/UIPlugin.js'
 import type { Body, Meta } from '@uppy/utils/lib/UppyFile'
 import type { ChangeEvent } from 'preact/compat'
 import toArray from '@uppy/utils/lib/toArray'
diff --git a/packages/@uppy/drop-target/src/index.ts b/packages/@uppy/drop-target/src/index.ts
index 5bc64b4301..db7fdc829b 100644
--- a/packages/@uppy/drop-target/src/index.ts
+++ b/packages/@uppy/drop-target/src/index.ts
@@ -1,5 +1,5 @@
 import type { Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { Uppy } from '@uppy/core/lib/Uppy'
+import type { Uppy } from '@uppy/core/lib/Uppy.js'
 import type { DefinePluginOpts, PluginOpts } from '@uppy/core/lib/BasePlugin.js'
 import BasePlugin from '@uppy/core/lib/BasePlugin.js'
 import getDroppedFiles from '@uppy/utils/lib/getDroppedFiles'
diff --git a/packages/@uppy/dropbox/src/Dropbox.tsx b/packages/@uppy/dropbox/src/Dropbox.tsx
index aea4b93370..17082dc561 100644
--- a/packages/@uppy/dropbox/src/Dropbox.tsx
+++ b/packages/@uppy/dropbox/src/Dropbox.tsx
@@ -9,7 +9,7 @@ import { ProviderViews } from '@uppy/provider-views'
 import { h, type ComponentChild } from 'preact'
 
 import type { UppyFile, Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy'
+import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy.js'
 import locale from './locale.ts'
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
 // @ts-ignore We don't want TS to generate types for the package.json
diff --git a/packages/@uppy/facebook/src/Facebook.tsx b/packages/@uppy/facebook/src/Facebook.tsx
index b1b8158073..fdf253a576 100644
--- a/packages/@uppy/facebook/src/Facebook.tsx
+++ b/packages/@uppy/facebook/src/Facebook.tsx
@@ -9,7 +9,7 @@ import { ProviderViews } from '@uppy/provider-views'
 import { h, type ComponentChild } from 'preact'
 
 import type { UppyFile, Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy'
+import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy.js'
 import locale from './locale.ts'
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
 // @ts-ignore We don't want TS to generate types for the package.json
diff --git a/packages/@uppy/golden-retriever/src/index.ts b/packages/@uppy/golden-retriever/src/index.ts
index 2ff90daffc..acea945de5 100644
--- a/packages/@uppy/golden-retriever/src/index.ts
+++ b/packages/@uppy/golden-retriever/src/index.ts
@@ -1,6 +1,6 @@
 import throttle from 'lodash/throttle.js'
 import BasePlugin from '@uppy/core/lib/BasePlugin.js'
-import type { PluginOpts, DefinePluginOpts } from '@uppy/core/lib/BasePlugin'
+import type { PluginOpts, DefinePluginOpts } from '@uppy/core/lib/BasePlugin.js'
 import type { Body, Meta, UppyFile } from '@uppy/utils/lib/UppyFile'
 import type Uppy from '@uppy/core'
 import type { UploadResult } from '@uppy/core'
diff --git a/packages/@uppy/google-drive/src/DriveProviderViews.ts b/packages/@uppy/google-drive/src/DriveProviderViews.ts
index fe0bfb8e3a..3ea16e5da3 100644
--- a/packages/@uppy/google-drive/src/DriveProviderViews.ts
+++ b/packages/@uppy/google-drive/src/DriveProviderViews.ts
@@ -1,7 +1,7 @@
 import type {
   PartialTreeFile,
   PartialTreeFolderNode,
-} from '@uppy/core/lib/Uppy'
+} from '@uppy/core/lib/Uppy.js'
 import { ProviderViews } from '@uppy/provider-views'
 import type { Body, Meta } from '@uppy/utils/lib/UppyFile'
 
diff --git a/packages/@uppy/google-drive/src/GoogleDrive.tsx b/packages/@uppy/google-drive/src/GoogleDrive.tsx
index 2ac20663fd..028d8ee287 100644
--- a/packages/@uppy/google-drive/src/GoogleDrive.tsx
+++ b/packages/@uppy/google-drive/src/GoogleDrive.tsx
@@ -9,7 +9,7 @@ import { ProviderViews } from '@uppy/provider-views'
 import { h, type ComponentChild } from 'preact'
 
 import type { UppyFile, Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy'
+import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy.js'
 import DriveProviderViews from './DriveProviderViews.ts'
 import locale from './locale.ts'
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
diff --git a/packages/@uppy/google-photos/src/GooglePhotos.tsx b/packages/@uppy/google-photos/src/GooglePhotos.tsx
index 81df409d6c..eba6bbb3e2 100644
--- a/packages/@uppy/google-photos/src/GooglePhotos.tsx
+++ b/packages/@uppy/google-photos/src/GooglePhotos.tsx
@@ -9,7 +9,7 @@ import {
 import { h, type ComponentChild } from 'preact'
 
 import type { UppyFile, Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy.ts'
+import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy.js'
 
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
 // @ts-ignore We don't want TS to generate types for the package.json
diff --git a/packages/@uppy/instagram/src/Instagram.tsx b/packages/@uppy/instagram/src/Instagram.tsx
index 1b8fb56da1..4c85265c20 100644
--- a/packages/@uppy/instagram/src/Instagram.tsx
+++ b/packages/@uppy/instagram/src/Instagram.tsx
@@ -9,7 +9,7 @@ import { ProviderViews } from '@uppy/provider-views'
 import { h, type ComponentChild } from 'preact'
 
 import type { UppyFile, Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy'
+import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy.js'
 import locale from './locale.ts'
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
 // @ts-ignore We don't want TS to generate types for the package.json
diff --git a/packages/@uppy/onedrive/src/OneDrive.tsx b/packages/@uppy/onedrive/src/OneDrive.tsx
index 6004cf96e6..b954058a6f 100644
--- a/packages/@uppy/onedrive/src/OneDrive.tsx
+++ b/packages/@uppy/onedrive/src/OneDrive.tsx
@@ -9,7 +9,7 @@ import { ProviderViews } from '@uppy/provider-views'
 import { h, type ComponentChild } from 'preact'
 
 import type { UppyFile, Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy'
+import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy.js'
 import locale from './locale.ts'
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
 // @ts-ignore We don't want TS to generate types for the package.json
diff --git a/packages/@uppy/progress-bar/src/ProgressBar.tsx b/packages/@uppy/progress-bar/src/ProgressBar.tsx
index 549b3b65b3..f4a5d9ac69 100644
--- a/packages/@uppy/progress-bar/src/ProgressBar.tsx
+++ b/packages/@uppy/progress-bar/src/ProgressBar.tsx
@@ -1,6 +1,6 @@
 import { h, type ComponentChild } from 'preact'
 import { UIPlugin, type UIPluginOptions } from '@uppy/core'
-import type { Uppy, State } from '@uppy/core/lib/Uppy'
+import type { Uppy, State } from '@uppy/core/lib/Uppy.js'
 import type { Body, Meta } from '@uppy/utils/lib/UppyFile'
 import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin.js'
 
diff --git a/packages/@uppy/provider-views/src/Breadcrumbs.tsx b/packages/@uppy/provider-views/src/Breadcrumbs.tsx
index f7d1c8d205..16f2c39e21 100644
--- a/packages/@uppy/provider-views/src/Breadcrumbs.tsx
+++ b/packages/@uppy/provider-views/src/Breadcrumbs.tsx
@@ -1,4 +1,4 @@
-import type { PartialTreeFolder } from '@uppy/core/lib/Uppy'
+import type { PartialTreeFolder } from '@uppy/core/lib/Uppy.js'
 import { h, Fragment } from 'preact'
 import type { Body, Meta } from '@uppy/utils/lib/UppyFile'
 import type ProviderView from './ProviderView/index.js'
diff --git a/packages/@uppy/provider-views/src/Browser.tsx b/packages/@uppy/provider-views/src/Browser.tsx
index 68a6e2bccd..fde01159c4 100644
--- a/packages/@uppy/provider-views/src/Browser.tsx
+++ b/packages/@uppy/provider-views/src/Browser.tsx
@@ -8,7 +8,7 @@ import type { I18n } from '@uppy/utils/lib/Translator'
 import type {
   PartialTreeFile,
   PartialTreeFolderNode,
-} from '@uppy/core/lib/Uppy.ts'
+} from '@uppy/core/lib/Uppy.js'
 import { useEffect, useState } from 'preact/hooks'
 import Item from './Item/index.tsx'
 import ProviderView from './ProviderView/ProviderView.tsx'
diff --git a/packages/@uppy/provider-views/src/FooterActions.tsx b/packages/@uppy/provider-views/src/FooterActions.tsx
index b297d5424f..db73fdd266 100644
--- a/packages/@uppy/provider-views/src/FooterActions.tsx
+++ b/packages/@uppy/provider-views/src/FooterActions.tsx
@@ -2,7 +2,7 @@ import { h } from 'preact'
 import type { I18n } from '@uppy/utils/lib/Translator'
 import type { Meta, Body } from '@uppy/utils/lib/UppyFile'
 import classNames from 'classnames'
-import type { PartialTree } from '@uppy/core/lib/Uppy'
+import type { PartialTree } from '@uppy/core/lib/Uppy.js'
 import { useMemo } from 'preact/hooks'
 import getNumberOfSelectedFiles from './utils/PartialTreeUtils/getNumberOfSelectedFiles.ts'
 import ProviderView from './ProviderView/ProviderView.tsx'
diff --git a/packages/@uppy/provider-views/src/Item/components/GridItem.tsx b/packages/@uppy/provider-views/src/Item/components/GridItem.tsx
index 74b7f7c9bc..e2593fbb62 100644
--- a/packages/@uppy/provider-views/src/Item/components/GridItem.tsx
+++ b/packages/@uppy/provider-views/src/Item/components/GridItem.tsx
@@ -2,7 +2,7 @@ import { h } from 'preact'
 import type {
   PartialTreeFile,
   PartialTreeFolderNode,
-} from '@uppy/core/lib/Uppy'
+} from '@uppy/core/lib/Uppy.js'
 import ItemIcon from './ItemIcon.tsx'
 
 type GridItemProps = {
diff --git a/packages/@uppy/provider-views/src/Item/components/ListItem.tsx b/packages/@uppy/provider-views/src/Item/components/ListItem.tsx
index b129a0d50f..8c7fc03297 100644
--- a/packages/@uppy/provider-views/src/Item/components/ListItem.tsx
+++ b/packages/@uppy/provider-views/src/Item/components/ListItem.tsx
@@ -2,7 +2,7 @@ import type {
   PartialTreeFile,
   PartialTreeFolderNode,
   PartialTreeId,
-} from '@uppy/core/lib/Uppy'
+} from '@uppy/core/lib/Uppy.js'
 import { h } from 'preact'
 import ItemIcon from './ItemIcon.tsx'
 
diff --git a/packages/@uppy/provider-views/src/Item/index.tsx b/packages/@uppy/provider-views/src/Item/index.tsx
index 8fbf88cbd5..879e8a24a6 100644
--- a/packages/@uppy/provider-views/src/Item/index.tsx
+++ b/packages/@uppy/provider-views/src/Item/index.tsx
@@ -7,7 +7,7 @@ import type {
   PartialTreeFile,
   PartialTreeFolderNode,
   PartialTreeId,
-} from '@uppy/core/lib/Uppy.ts'
+} from '@uppy/core/lib/Uppy.js'
 import GridItem from './components/GridItem.tsx'
 import ListItem from './components/ListItem.tsx'
 
diff --git a/packages/@uppy/provider-views/src/ProviderView/Header.tsx b/packages/@uppy/provider-views/src/ProviderView/Header.tsx
index 699a4ec947..486d15d19d 100644
--- a/packages/@uppy/provider-views/src/ProviderView/Header.tsx
+++ b/packages/@uppy/provider-views/src/ProviderView/Header.tsx
@@ -2,7 +2,7 @@
 import { h } from 'preact'
 import type { I18n } from '@uppy/utils/lib/Translator'
 import type { Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { PartialTreeFolder } from '@uppy/core/lib/Uppy.ts'
+import type { PartialTreeFolder } from '@uppy/core/lib/Uppy.js'
 import classNames from 'classnames'
 import User from './User.tsx'
 import Breadcrumbs from '../Breadcrumbs.tsx'
diff --git a/packages/@uppy/provider-views/src/ProviderView/ProviderView.tsx b/packages/@uppy/provider-views/src/ProviderView/ProviderView.tsx
index 12389f4bdf..8dc9ed28d2 100644
--- a/packages/@uppy/provider-views/src/ProviderView/ProviderView.tsx
+++ b/packages/@uppy/provider-views/src/ProviderView/ProviderView.tsx
@@ -7,12 +7,12 @@ import type {
   UnknownProviderPluginState,
   PartialTreeId,
   PartialTree,
-} from '@uppy/core/lib/Uppy.ts'
+} from '@uppy/core/lib/Uppy.js'
 import type { Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { CompanionFile } from '@uppy/utils/lib/CompanionFile.ts'
+import type { CompanionFile } from '@uppy/utils/lib/CompanionFile'
 import type Translator from '@uppy/utils/lib/Translator'
 import classNames from 'classnames'
-import type { ValidateableFile } from '@uppy/core/lib/Restricter.ts'
+import type { ValidateableFile } from '@uppy/core/lib/Restricter.js'
 import remoteFileObjToLocal from '@uppy/utils/lib/remoteFileObjToLocal'
 import AuthView from './AuthView.tsx'
 import Header from './Header.tsx'
diff --git a/packages/@uppy/provider-views/src/SearchProviderView/SearchProviderView.tsx b/packages/@uppy/provider-views/src/SearchProviderView/SearchProviderView.tsx
index 977492f03d..786bafb59d 100644
--- a/packages/@uppy/provider-views/src/SearchProviderView/SearchProviderView.tsx
+++ b/packages/@uppy/provider-views/src/SearchProviderView/SearchProviderView.tsx
@@ -8,10 +8,10 @@ import type {
   PartialTreeFolderRoot,
   UnknownSearchProviderPlugin,
   UnknownSearchProviderPluginState,
-} from '@uppy/core/lib/Uppy.ts'
+} from '@uppy/core/lib/Uppy.js'
 import type { CompanionFile } from '@uppy/utils/lib/CompanionFile'
 import classNames from 'classnames'
-import type { ValidateableFile } from '@uppy/core/lib/Restricter.ts'
+import type { ValidateableFile } from '@uppy/core/lib/Restricter.js'
 import remoteFileObjToLocal from '@uppy/utils/lib/remoteFileObjToLocal'
 import SearchInput from '../SearchInput.tsx'
 import Browser from '../Browser.tsx'
diff --git a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterFill.ts b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterFill.ts
index c95f75785c..87eefd2151 100644
--- a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterFill.ts
+++ b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterFill.ts
@@ -4,7 +4,7 @@ import type {
   PartialTreeFile,
   PartialTreeFolderNode,
   PartialTreeId,
-} from '@uppy/core/lib/Uppy'
+} from '@uppy/core/lib/Uppy.js'
 import type { CompanionFile } from '@uppy/utils/lib/CompanionFile'
 import PQueue from 'p-queue'
 import shallowClone from './shallowClone.ts'
diff --git a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterOpenFolder.ts b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterOpenFolder.ts
index eed1fcc6d9..182fc1f6ab 100644
--- a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterOpenFolder.ts
+++ b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterOpenFolder.ts
@@ -3,7 +3,7 @@ import type {
   PartialTreeFile,
   PartialTreeFolder,
   PartialTreeFolderNode,
-} from '@uppy/core/lib/Uppy'
+} from '@uppy/core/lib/Uppy.js'
 import type { CompanionFile } from '@uppy/utils/lib/CompanionFile'
 
 const afterOpenFolder = (
diff --git a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterScrollFolder.ts b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterScrollFolder.ts
index 854922a89f..632c970172 100644
--- a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterScrollFolder.ts
+++ b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterScrollFolder.ts
@@ -4,7 +4,7 @@ import type {
   PartialTreeFolder,
   PartialTreeFolderNode,
   PartialTreeId,
-} from '@uppy/core/lib/Uppy'
+} from '@uppy/core/lib/Uppy.js'
 import type { CompanionFile } from '@uppy/utils/lib/CompanionFile'
 
 const afterScrollFolder = (
diff --git a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterToggleCheckbox.ts b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterToggleCheckbox.ts
index 911f7baab2..3d5da3ac28 100644
--- a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterToggleCheckbox.ts
+++ b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/afterToggleCheckbox.ts
@@ -5,7 +5,7 @@ import type {
   PartialTreeFolder,
   PartialTreeFolderNode,
   PartialTreeId,
-} from '@uppy/core/lib/Uppy'
+} from '@uppy/core/lib/Uppy.js'
 import shallowClone from './shallowClone.ts'
 
 /*
diff --git a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/getBreadcrumbs.ts b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/getBreadcrumbs.ts
index 5620a0b7bf..9a19424725 100644
--- a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/getBreadcrumbs.ts
+++ b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/getBreadcrumbs.ts
@@ -3,7 +3,7 @@ import type {
   PartialTreeFolder,
   PartialTreeFolderNode,
   PartialTreeId,
-} from '@uppy/core/lib/Uppy'
+} from '@uppy/core/lib/Uppy.js'
 
 const getBreadcrumbs = (
   partialTree: PartialTree,
diff --git a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/getCheckedFilesWithPaths.ts b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/getCheckedFilesWithPaths.ts
index a438a654fa..8ebc725403 100644
--- a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/getCheckedFilesWithPaths.ts
+++ b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/getCheckedFilesWithPaths.ts
@@ -4,7 +4,7 @@ import type {
   PartialTreeFile,
   PartialTreeFolderNode,
   PartialTreeId,
-} from '@uppy/core/lib/Uppy'
+} from '@uppy/core/lib/Uppy.js'
 import type { CompanionFile } from '@uppy/utils/lib/CompanionFile'
 
 export interface Cache {
diff --git a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/getNumberOfSelectedFiles.ts b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/getNumberOfSelectedFiles.ts
index d27a3e18f7..3d8635f13f 100644
--- a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/getNumberOfSelectedFiles.ts
+++ b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/getNumberOfSelectedFiles.ts
@@ -1,4 +1,4 @@
-import type { PartialTree } from '@uppy/core/lib/Uppy'
+import type { PartialTree } from '@uppy/core/lib/Uppy.js'
 
 /**
  * We're interested in all 'checked' leaves of this tree,
diff --git a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/index.test.ts b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/index.test.ts
index fd744275b2..fc1845a632 100644
--- a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/index.test.ts
+++ b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/index.test.ts
@@ -7,7 +7,7 @@ import type {
   PartialTreeFolderNode,
   PartialTreeFolderRoot,
   PartialTreeId,
-} from '@uppy/core/lib/Uppy.ts'
+} from '@uppy/core/lib/Uppy.js'
 import afterToggleCheckbox from './afterToggleCheckbox.ts'
 import afterOpenFolder from './afterOpenFolder.ts'
 import afterScrollFolder from './afterScrollFolder.ts'
diff --git a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/shallowClone.ts b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/shallowClone.ts
index c81cda89f3..fa61ed586c 100644
--- a/packages/@uppy/provider-views/src/utils/PartialTreeUtils/shallowClone.ts
+++ b/packages/@uppy/provider-views/src/utils/PartialTreeUtils/shallowClone.ts
@@ -1,4 +1,4 @@
-import type { PartialTree } from '@uppy/core/lib/Uppy'
+import type { PartialTree } from '@uppy/core/lib/Uppy.js'
 
 /**
  * One-level copying is sufficient as mutations within our `partialTree` are limited to properties
diff --git a/packages/@uppy/provider-views/src/utils/getClickedRange.ts b/packages/@uppy/provider-views/src/utils/getClickedRange.ts
index 7279f85735..637885f0fa 100644
--- a/packages/@uppy/provider-views/src/utils/getClickedRange.ts
+++ b/packages/@uppy/provider-views/src/utils/getClickedRange.ts
@@ -1,7 +1,7 @@
 import type {
   PartialTreeFile,
   PartialTreeFolderNode,
-} from '@uppy/core/lib/Uppy'
+} from '@uppy/core/lib/Uppy.js'
 
 // Shift-clicking selects a single consecutive list of items
 // starting at the previous click.
diff --git a/packages/@uppy/remote-sources/src/index.ts b/packages/@uppy/remote-sources/src/index.ts
index 9cc9c78108..5c24cd2e1d 100644
--- a/packages/@uppy/remote-sources/src/index.ts
+++ b/packages/@uppy/remote-sources/src/index.ts
@@ -15,7 +15,7 @@ import Unsplash from '@uppy/unsplash'
 import Url from '@uppy/url'
 import Zoom from '@uppy/zoom'
 
-import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin'
+import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin.js'
 import type { Body, Meta } from '@uppy/utils/lib/UppyFile'
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
 // @ts-ignore We don't want TS to generate types for the package.json
diff --git a/packages/@uppy/screen-capture/src/ScreenCapture.tsx b/packages/@uppy/screen-capture/src/ScreenCapture.tsx
index a71edc56e4..7414bed088 100644
--- a/packages/@uppy/screen-capture/src/ScreenCapture.tsx
+++ b/packages/@uppy/screen-capture/src/ScreenCapture.tsx
@@ -1,7 +1,7 @@
 import { h, type ComponentChild } from 'preact'
 import { UIPlugin, Uppy, type UIPluginOptions } from '@uppy/core'
 import getFileTypeExtension from '@uppy/utils/lib/getFileTypeExtension'
-import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin'
+import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin.js'
 import type { Body, Meta } from '@uppy/utils/lib/UppyFile'
 import ScreenRecIcon from './ScreenRecIcon.tsx'
 import RecorderScreen from './RecorderScreen.tsx'
diff --git a/packages/@uppy/status-bar/src/Components.tsx b/packages/@uppy/status-bar/src/Components.tsx
index d79ea981db..fa096c95a0 100644
--- a/packages/@uppy/status-bar/src/Components.tsx
+++ b/packages/@uppy/status-bar/src/Components.tsx
@@ -1,5 +1,5 @@
 import type { Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { State, Uppy } from '@uppy/core/lib/Uppy'
+import type { State, Uppy } from '@uppy/core/lib/Uppy.js'
 import type { FileProcessingInfo } from '@uppy/utils/lib/FileProgress'
 import type { I18n } from '@uppy/utils/lib/Translator'
 import { h } from 'preact'
diff --git a/packages/@uppy/status-bar/src/StatusBar.tsx b/packages/@uppy/status-bar/src/StatusBar.tsx
index 04d59ffa4e..c445f8035a 100644
--- a/packages/@uppy/status-bar/src/StatusBar.tsx
+++ b/packages/@uppy/status-bar/src/StatusBar.tsx
@@ -1,7 +1,7 @@
 import type { ComponentChild } from 'preact'
 import type { Body, Meta, UppyFile } from '@uppy/utils/lib/UppyFile'
-import type { Uppy, State } from '@uppy/core/lib/Uppy'
-import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin'
+import type { Uppy, State } from '@uppy/core/lib/Uppy.js'
+import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin.js'
 import { UIPlugin } from '@uppy/core'
 import emaFilter from '@uppy/utils/lib/emaFilter'
 import getTextDirection from '@uppy/utils/lib/getTextDirection'
diff --git a/packages/@uppy/status-bar/src/StatusBarOptions.ts b/packages/@uppy/status-bar/src/StatusBarOptions.ts
index f2f9f4f6d7..83e157da91 100644
--- a/packages/@uppy/status-bar/src/StatusBarOptions.ts
+++ b/packages/@uppy/status-bar/src/StatusBarOptions.ts
@@ -1,4 +1,4 @@
-import type { UIPluginOptions } from '@uppy/core/lib/UIPlugin'
+import type { UIPluginOptions } from '@uppy/core/lib/UIPlugin.js'
 import type StatusBarLocale from './locale.js'
 
 export interface StatusBarOptions extends UIPluginOptions {
diff --git a/packages/@uppy/status-bar/src/StatusBarUI.tsx b/packages/@uppy/status-bar/src/StatusBarUI.tsx
index 1fab564067..c688201853 100644
--- a/packages/@uppy/status-bar/src/StatusBarUI.tsx
+++ b/packages/@uppy/status-bar/src/StatusBarUI.tsx
@@ -1,6 +1,6 @@
 import type { Body, Meta, UppyFile } from '@uppy/utils/lib/UppyFile'
 import type { I18n } from '@uppy/utils/lib/Translator'
-import type { Uppy, State } from '@uppy/core/lib/Uppy'
+import type { Uppy, State } from '@uppy/core/lib/Uppy.js'
 import { h } from 'preact'
 import classNames from 'classnames'
 import statusBarStates from './StatusBarStates.ts'
diff --git a/packages/@uppy/thumbnail-generator/src/index.ts b/packages/@uppy/thumbnail-generator/src/index.ts
index d0205de2b1..45ce9d3499 100644
--- a/packages/@uppy/thumbnail-generator/src/index.ts
+++ b/packages/@uppy/thumbnail-generator/src/index.ts
@@ -6,7 +6,7 @@ import isPreviewSupported from '@uppy/utils/lib/isPreviewSupported'
 // @ts-ignore untyped
 import { rotation } from 'exifr/dist/mini.esm.mjs'
 
-import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin'
+import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin.js'
 import type { Body, Meta, UppyFile } from '@uppy/utils/lib/UppyFile'
 import locale from './locale.ts'
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
diff --git a/packages/@uppy/unsplash/src/Unsplash.tsx b/packages/@uppy/unsplash/src/Unsplash.tsx
index 932a569179..fbbf5dcc5f 100644
--- a/packages/@uppy/unsplash/src/Unsplash.tsx
+++ b/packages/@uppy/unsplash/src/Unsplash.tsx
@@ -9,7 +9,7 @@ import { SearchProviderViews } from '@uppy/provider-views'
 import { h, type ComponentChild } from 'preact'
 
 import type { UppyFile, Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { UnknownSearchProviderPluginState } from '@uppy/core/lib/Uppy'
+import type { UnknownSearchProviderPluginState } from '@uppy/core/lib/Uppy.js'
 import locale from './locale.ts'
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
 // @ts-ignore We don't want TS to generate types for the package.json
diff --git a/packages/@uppy/webcam/src/Webcam.tsx b/packages/@uppy/webcam/src/Webcam.tsx
index b65221aab0..0201dc77bd 100644
--- a/packages/@uppy/webcam/src/Webcam.tsx
+++ b/packages/@uppy/webcam/src/Webcam.tsx
@@ -2,13 +2,13 @@ import { h, type ComponentChild } from 'preact'
 
 import { UIPlugin } from '@uppy/core'
 import type { Uppy, UIPluginOptions } from '@uppy/core'
-import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin'
+import type { DefinePluginOpts } from '@uppy/core/lib/BasePlugin.js'
 import type {
   Body,
   Meta,
   MinimalRequiredUppyFile,
-} from '@uppy/utils/lib/UppyFile.ts'
-import type { PluginTarget } from '@uppy/core/lib/UIPlugin'
+} from '@uppy/utils/lib/UppyFile'
+import type { PluginTarget } from '@uppy/core/lib/UIPlugin.js'
 import getFileTypeExtension from '@uppy/utils/lib/getFileTypeExtension'
 import mimeTypes from '@uppy/utils/lib/mimeTypes'
 import isMobile from 'is-mobile'
diff --git a/packages/@uppy/zoom/src/Zoom.tsx b/packages/@uppy/zoom/src/Zoom.tsx
index 81c6bacf3c..888e359a01 100644
--- a/packages/@uppy/zoom/src/Zoom.tsx
+++ b/packages/@uppy/zoom/src/Zoom.tsx
@@ -9,7 +9,7 @@ import { ProviderViews } from '@uppy/provider-views'
 import { h, type ComponentChild } from 'preact'
 
 import type { UppyFile, Body, Meta } from '@uppy/utils/lib/UppyFile'
-import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy'
+import type { UnknownProviderPluginState } from '@uppy/core/lib/Uppy.js'
 import locale from './locale.ts'
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
 // @ts-ignore We don't want TS to generate types for the package.json