diff --git a/extension.json b/extension.json
index 90fdbe8cc..dfcd21adb 100644
--- a/extension.json
+++ b/extension.json
@@ -155,23 +155,6 @@
 				"resources/ext.popups/index.js"
 			]
 		},
-		"ext.popups.referencePreviews": {
-			"dependencies": [
-				"ext.popups.main"
-			],
-			"styles": [
-				"resources/ext.popups.referencePreviews/referencePreview.less"
-			],
-			"packageFiles": [
-				"resources/ext.popups.referencePreviews/index.js",
-				"resources/ext.popups.referencePreviews/constants.js",
-				"resources/ext.popups.referencePreviews/createReferenceGateway.js",
-				"resources/ext.popups.referencePreviews/createReferencePreview.js",
-				"resources/ext.popups.referencePreviews/isReferencePreviewsEnabled.js",
-				"resources/ext.popups.referencePreviews/referencePreviews.js",
-				"resources/ext.popups.referencePreviews/setUserConfigFlags.js"
-			]
-		},
 		"ext.popups.main": {
 			"class": "MediaWiki\\ResourceLoader\\CodexModule",
 			"codexStyleOnly": true,
diff --git a/includes/PopupsHooks.php b/includes/PopupsHooks.php
index cfa20d538..c13979221 100644
--- a/includes/PopupsHooks.php
+++ b/includes/PopupsHooks.php
@@ -27,7 +27,6 @@ use MediaWiki\Hook\BeforePageDisplayHook;
 use MediaWiki\Hook\MakeGlobalVariablesScriptHook;
 use MediaWiki\Output\OutputPage;
 use MediaWiki\Preferences\Hook\GetPreferencesHook;
-use MediaWiki\ResourceLoader\Context;
 use MediaWiki\ResourceLoader\Hook\ResourceLoaderGetConfigVarsHook;
 use MediaWiki\User\Hook\UserGetDefaultOptionsHook;
 use MediaWiki\User\Options\UserOptionsManager;
@@ -83,18 +82,12 @@ class PopupsHooks implements
 
 	/**
 	 * Get custom Popups types registered by extensions
-	 * @param Context $context
 	 * @return array
 	 */
-	public static function getCustomPopupTypes( Context $context ): array {
-		// FIXME: If the module ext.cite.referencePreviews does not exist register reference previews.
-		// This code can be removed once T355194 is complete.
-		$others = $context->getResourceLoader()->getModule( 'ext.cite.referencePreviews' ) ?
-			[] : [ 'ext.popups.referencePreviews' ];
-
-		return array_merge( ExtensionRegistry::getInstance()->getAttribute(
+	public static function getCustomPopupTypes(): array {
+		return ExtensionRegistry::getInstance()->getAttribute(
 			'PopupsPluginModules'
-		), $others );
+		);
 	}
 
 	/**
diff --git a/resources/ext.popups.referencePreviews/OWNERS.md b/resources/ext.popups.referencePreviews/OWNERS.md
deleted file mode 100644
index ebf9c0bb0..000000000
--- a/resources/ext.popups.referencePreviews/OWNERS.md
+++ /dev/null
@@ -1 +0,0 @@
-Code in this folder and subfolders is maintained by WMDE.
diff --git a/resources/ext.popups.referencePreviews/constants.js b/resources/ext.popups.referencePreviews/constants.js
deleted file mode 100644
index 06be9a89f..000000000
--- a/resources/ext.popups.referencePreviews/constants.js
+++ /dev/null
@@ -1,4 +0,0 @@
-module.exports = {
-    TYPE_REFERENCE: 'reference',
-    FETCH_DELAY_REFERENCE_TYPE: 150
-};
diff --git a/resources/ext.popups.referencePreviews/createReferenceGateway.js b/resources/ext.popups.referencePreviews/createReferenceGateway.js
deleted file mode 100644
index 48dc4a759..000000000
--- a/resources/ext.popups.referencePreviews/createReferenceGateway.js
+++ /dev/null
@@ -1,94 +0,0 @@
-/**
- * @module gateway/reference
- */
-
-const { TYPE_REFERENCE } = require( './constants.js' );
-
-/**
- * @return {Gateway}
- */
-module.exports = function createReferenceGateway() {
-
-	/**
-	 * @param {string} id
-	 * @return {HTMLElement}
-	 */
-	function scrapeReferenceText( id ) {
-		const idSelector = `#${ CSS.escape( id ) }`;
-
-		/**
-		 * Same alternative selectors with and without mw-… as in the RESTbased endpoint.
-		 *
-		 * @see https://phabricator.wikimedia.org/diffusion/GMOA/browse/master/lib/transformations/references/structureReferenceListContent.js$138
-		 */
-		return document.querySelector( `${ idSelector } .mw-reference-text, ${ idSelector } .reference-text` );
-	}
-
-	/**
-	 * Attempts to find a single reference type identifier, limited to a list of known types.
-	 * - When a `class="…"` attribute mentions multiple known types, the last one is used, following
-	 *   CSS semantics.
-	 * - When there are multiple <cite> tags, the first with a known type is used.
-	 *
-	 * @param {HTMLElement} referenceText
-	 * @return {string|null}
-	 */
-	function scrapeReferenceType( referenceText ) {
-		const KNOWN_TYPES = [ 'book', 'journal', 'news', 'note', 'web' ];
-		let type = null;
-		const citeTags = referenceText.querySelectorAll( 'cite[class]' );
-		Array.prototype.forEach.call( citeTags, ( element ) => {
-			// don't need to keep scanning if one is found.
-			if ( type ) {
-				return;
-			}
-			const classNames = element.className.split( /\s+/ );
-			for ( let i = classNames.length; i--; ) {
-				if ( KNOWN_TYPES.indexOf( classNames[ i ] ) !== -1 ) {
-					type = classNames[ i ];
-					return false;
-				}
-			}
-		} );
-		return type;
-	}
-
-	/**
-	 * @param {mw.Title} title
-	 * @param {HTMLAnchorElement} el
-	 * @return {AbortPromise<ReferencePreviewModel>}
-	 */
-	function fetchPreviewForTitle( title, el ) {
-		// Need to encode the fragment again as mw.Title returns it as decoded text
-		const id = title.getFragment().replace( / /g, '_' ),
-			referenceNode = scrapeReferenceText( id );
-
-		if ( !referenceNode ||
-			// Skip references that don't contain anything but whitespace, e.g. a single &nbsp;
-			( !referenceNode.textContent.trim() && !referenceNode.children.length )
-		) {
-			return Promise.reject(
-				// Required to set `showNullPreview` to false and not open an error popup
-				{ textStatus: 'abort', textContext: 'Footnote not found or empty', xhr: { readyState: 0 } }
-			);
-		}
-
-		const model = {
-			url: `#${ id }`,
-			extract: referenceNode.innerHTML,
-			type: TYPE_REFERENCE,
-			referenceType: scrapeReferenceType( referenceNode ),
-			// Note: Even the top-most HTMLHtmlElement is guaranteed to have a parent.
-			sourceElementId: el.parentNode.id
-		};
-
-		// Make promise abortable.
-		const promise = Promise.resolve( model );
-		promise.abort = () => {};
-		return promise;
-	}
-
-	return {
-		fetchPreviewForTitle
-	};
-}
diff --git a/resources/ext.popups.referencePreviews/createReferencePreview.js b/resources/ext.popups.referencePreviews/createReferencePreview.js
deleted file mode 100644
index 46b99750e..000000000
--- a/resources/ext.popups.referencePreviews/createReferencePreview.js
+++ /dev/null
@@ -1,191 +0,0 @@
-/**
- * @module referencePreview
- */
-const { isTrackingEnabled, LOGGING_SCHEMA } = require( './referencePreviews.js' );
-
-const TEMPLATE = document.createElement( 'template' );
-TEMPLATE.innerHTML = `
-<div class="mwe-popups mwe-popups mwe-popups-type-reference" aria-hidden>
-	<div class="mwe-popups-container">
-		<div class="mwe-popups-extract">
-			<div class="mwe-popups-scroll">
-				<strong class="mwe-popups-title">
-					<span class="popups-icon"></span>
-					<span class="mwe-popups-title-placeholder"></span>
-				</strong>
-				<bdi><div class="mw-parser-output"></div></bdi>
-			</div>
-			<div class="mwe-popups-fade"></div>
-		</div>
-		<footer>
-			<div class="mwe-popups-settings"></div>
-		</footer>
-	</div>
-</div>`;
-
-/**
- * @param {HTMLElement} node
- * @param {HTMLElement|string} htmlOrOtherNode
- */
-const replaceWith = ( node, htmlOrOtherNode ) => {
-	if ( typeof htmlOrOtherNode === 'string' ) {
-		node.insertAdjacentHTML( 'afterend', htmlOrOtherNode );
-	} else {
-		node.parentNode.appendChild( htmlOrOtherNode );
-	}
-	node.remove();
-};
-
-/**
- * @param {ext.popups.ReferencePreviewModel} model
- * @return {jQuery}
- */
-function renderReferencePreview(
-	model
-) {
-	const type = model.referenceType || 'generic';
-	// The following messages are used here:
-	// * popups-refpreview-book
-	// * popups-refpreview-journal
-	// * popups-refpreview-news
-	// * popups-refpreview-note
-	// * popups-refpreview-web
-	let titleMsg = mw.message( `popups-refpreview-${ type }` );
-	if ( !titleMsg.exists() ) {
-		titleMsg = mw.message( 'popups-refpreview-reference' );
-	}
-
-	const el = TEMPLATE.content.cloneNode( true ).children[ 0 ];
-
-	replaceWith(
-		el.querySelector( '.mwe-popups-title-placeholder' ),
-		mw.html.escape( titleMsg.text() )
-	);
-	// The following classes are used here:
-	// * popups-icon--reference-generic
-	// * popups-icon--reference-book
-	// * popups-icon--reference-journal
-	// * popups-icon--reference-news
-	// * popups-icon--reference-note
-	// * popups-icon--reference-web
-	el.querySelector( '.mwe-popups-title .popups-icon' )
-		.classList.add( `popups-icon--reference-${ type }` );
-	el.querySelector( '.mw-parser-output' )
-		.innerHTML = model.extract;
-
-	// Make sure to not destroy existing targets, if any
-	Array.prototype.forEach.call(
-		el.querySelectorAll( '.mwe-popups-extract a[href][class~="external"]:not([target])' ),
-		( a ) => {
-			a.target = '_blank';
-			// Don't let the external site access and possibly manipulate window.opener.location
-			a.rel = `${ a.rel ? `${ a.rel } ` : '' }noopener`;
-		}
-	);
-
-	// We assume elements that benefit from being collapsible are to large for the popup
-	Array.prototype.forEach.call( el.querySelectorAll( '.mw-collapsible' ), ( node ) => {
-		const otherNode = document.createElement( 'div' );
-		otherNode.classList.add( 'mwe-collapsible-placeholder' );
-		const icon = document.createElement( 'span' );
-		icon.classList.add( 'popups-icon', 'popups-icon--infoFilled' );
-		const label = document.createElement( 'span' );
-		label.classList.add( 'mwe-collapsible-placeholder-label' );
-		label.textContent = mw.msg( 'popups-refpreview-collapsible-placeholder' );
-		otherNode.appendChild( icon );
-		otherNode.appendChild( label );
-		replaceWith( node, otherNode );
-	} );
-
-	// Undo remaining effects from the jquery.tablesorter.js plugin
-	const undoHeaderSort = ( headerSort ) => {
-		headerSort.classList.remove( 'headerSort' );
-		headerSort.removeAttribute( 'tabindex' );
-		headerSort.removeAttribute( 'title' );
-	};
-	Array.prototype.forEach.call( el.querySelectorAll( 'table.sortable' ), ( node ) => {
-		node.classList.remove( 'sortable', 'jquery-tablesorter' );
-		Array.prototype.forEach.call( node.querySelectorAll( '.headerSort' ), undoHeaderSort );
-	} );
-
-	// TODO: Do not remove this but move it up into the templateHTML constant!
-	const settingsButton = document.createElement( 'a' );
-	settingsButton.classList.add( 'cdx-button', 'cdx-button--fake-button', 'cdx-button--fake-button--enabled', 'cdx-button--weight-quiet', 'cdx-button--icon-only', 'mwe-popups-settings-button' );
-	const settingsIcon = document.createElement( 'span' );
-	settingsIcon.classList.add( 'popups-icon', 'popups-icon--size-small', 'popups-icon--settings' );
-	const settingsButtonLabel = document.createElement( 'span' );
-	settingsButtonLabel.textContent = mw.msg( 'popups-settings-icon-gear-title' );
-	settingsButton.append( settingsIcon );
-	settingsButton.append( settingsButtonLabel );
-	el.querySelector( '.mwe-popups-settings' ).appendChild( settingsButton );
-
-	if ( isTrackingEnabled() ) {
-		el.querySelector( '.mw-parser-output' ).addEventListener( 'click', ( ev ) => {
-			if ( !ev.target.matches( 'a' ) ) {
-				return;
-			}
-			mw.track( LOGGING_SCHEMA, {
-				action: 'clickedReferencePreviewsContentLink'
-			} );
-		} );
-	}
-
-	el.querySelector( '.mwe-popups-scroll' ).addEventListener( 'scroll', function ( e ) {
-		const element = e.target,
-			// We are dealing with floating point numbers here when the page is zoomed!
-			scrolledToBottom = element.scrollTop >= element.scrollHeight - element.clientHeight - 1;
-
-		if ( isTrackingEnabled() ) {
-			if ( !element.isOpenRecorded ) {
-				mw.track( LOGGING_SCHEMA, {
-					action: 'poppedOpen',
-					scrollbarsPresent: element.scrollHeight > element.clientHeight
-				} );
-				element.isOpenRecorded = true;
-			}
-
-			if (
-				element.scrollTop > 0 &&
-				!element.isScrollRecorded
-			) {
-				mw.track( LOGGING_SCHEMA, {
-					action: 'scrolled'
-				} );
-				element.isScrollRecorded = true;
-			}
-		}
-
-		if ( !scrolledToBottom && element.isScrolling ) {
-			return;
-		}
-
-		const extract = element.parentNode,
-			hasHorizontalScroll = element.scrollWidth > element.clientWidth,
-			scrollbarHeight = element.offsetHeight - element.clientHeight,
-			hasVerticalScroll = element.scrollHeight > element.clientHeight,
-			scrollbarWidth = element.offsetWidth - element.clientWidth;
-		const fade = extract.querySelector( '.mwe-popups-fade' );
-		fade.style.bottom = hasHorizontalScroll ? `${ scrollbarHeight }px` : 0;
-		fade.style.right = hasVerticalScroll ? `${ scrollbarWidth }px` : 0;
-
-		element.isScrolling = !scrolledToBottom;
-		extract.classList.toggle( 'mwe-popups-fade-out', element.isScrolling );
-		extract.setAttribute( 'lang', mw.config.get( 'wgPageContentLanguage' ) );
-	} );
-
-	return el;
-}
-
-/**
- * @param {ext.popups.ReferencePreviewModel} model
- * @return {ext.popups.Preview}
- */
-function createReferencePreview( model ) {
-	return {
-		el: renderReferencePreview( model ),
-		hasThumbnail: false,
-		isTall: false
-	};
-}
-
-module.exports = createReferencePreview;
diff --git a/resources/ext.popups.referencePreviews/index.js b/resources/ext.popups.referencePreviews/index.js
deleted file mode 100644
index 05a85e697..000000000
--- a/resources/ext.popups.referencePreviews/index.js
+++ /dev/null
@@ -1,37 +0,0 @@
-const isReferencePreviewsEnabled = require( './isReferencePreviewsEnabled.js' );
-const { initReferencePreviewsInstrumentation } = require( './referencePreviews.js' )
-const createReferenceGateway = require( './createReferenceGateway.js' )
-const renderFn  = require( './createReferencePreview.js' );
-const { TYPE_REFERENCE, FETCH_DELAY_REFERENCE_TYPE } = require( './constants.js' )
-const setUserConfigFlags = require( './setUserConfigFlags.js' )
-
-const REFERENCE_PREVIEWS_LOGGING_SCHEMA = 'event.ReferencePreviewsPopups';
-
-setUserConfigFlags( mw.config );
-const referencePreviewsState = isReferencePreviewsEnabled(
-	mw.user, mw.popups.isEnabled,
-	mw.config
-);
-const gateway = createReferenceGateway();
-
-// For tracking baseline stats in the Cite extension https://phabricator.wikimedia.org/T353798
-// FIXME: This might be obsolete when the code moves to the Cite extension and the tracking there
-//  can check that state differently.
-mw.config.set( 'wgPopupsReferencePreviewsVisible', !!referencePreviewsState );
-
-mw.trackSubscribe( 'Popups.SettingChange', ( data ) => {
-	if ( data.previewType === TYPE_REFERENCE ) {
-		mw.track( REFERENCE_PREVIEWS_LOGGING_SCHEMA, data );
-	}
-} );
-
-module.exports = referencePreviewsState !== null ? {
-	type: TYPE_REFERENCE,
-	selector: '#mw-content-text .reference a[ href*="#" ]',
-	delay: FETCH_DELAY_REFERENCE_TYPE,
-	gateway,
-	renderFn,
-	init: () => {
-		initReferencePreviewsInstrumentation();
-	}
-} : null;
diff --git a/resources/ext.popups.referencePreviews/isReferencePreviewsEnabled.js b/resources/ext.popups.referencePreviews/isReferencePreviewsEnabled.js
deleted file mode 100644
index e1dff0819..000000000
--- a/resources/ext.popups.referencePreviews/isReferencePreviewsEnabled.js
+++ /dev/null
@@ -1,41 +0,0 @@
-const { TYPE_REFERENCE } = require( './constants.js' );
-
-/**
- * @module isReferencePreviewsEnabled
- */
-
-/**
- * Given the global state of the application, creates a function that gets
- * whether or not the user should have Reference Previews enabled.
- *
- * @param {mw.User} user The `mw.user` singleton instance
- * @param {Function} isPreviewTypeEnabled check whether preview has been disabled or enabled.
- * @param {mw.Map} config
- *
- * @return {boolean|null} Null when there is no way the popup type can be enabled at run-time.
- */
-function isReferencePreviewsEnabled( user, isPreviewTypeEnabled, config ) {
-	// TODO: This and the final `mw.user.options` check are currently redundant. Only this here
-	// should be removed when the wgPopupsReferencePreviews feature flag is not needed any more.
-	if ( !config.get( 'wgPopupsReferencePreviews' ) ) {
-		return null;
-	}
-
-	// T265872: Unavailable when in conflict with (one of the) reference tooltips gadgets.
-	if ( config.get( 'wgPopupsConflictsWithRefTooltipsGadget' ) ||
-		config.get( 'wgPopupsConflictsWithNavPopupGadget' ) ||
-		// T243822: Temporarily disabled in the mobile skin
-		config.get( 'skin' ) === 'minerva'
-	) {
-		return null;
-	}
-
-	if ( user.isAnon() ) {
-		return isPreviewTypeEnabled( TYPE_REFERENCE );
-	}
-
-	// Registered users never can enable popup types at run-time.
-	return user.options.get( 'popups-reference-previews' ) === '1' ? true : null;
-}
-
-module.exports = isReferencePreviewsEnabled;
diff --git a/resources/ext.popups.referencePreviews/referencePreview.less b/resources/ext.popups.referencePreviews/referencePreview.less
deleted file mode 100644
index bc81b0b84..000000000
--- a/resources/ext.popups.referencePreviews/referencePreview.less
+++ /dev/null
@@ -1,81 +0,0 @@
-@import 'mediawiki.skin.variables.less';
-@import '../../src/ui/variables.less';
-
-.popups-icon--reference-generic {
-	.cdx-mixin-css-icon( @cdx-icon-reference );
-}
-
-.popups-icon--reference-book {
-	.cdx-mixin-css-icon( @cdx-icon-book );
-}
-
-.popups-icon--reference-journal {
-	.cdx-mixin-css-icon( @cdx-icon-journal );
-}
-
-.popups-icon--reference-news {
-	.cdx-mixin-css-icon( @cdx-icon-newspaper );
-}
-
-.popups-icon--reference-web {
-	.cdx-mixin-css-icon( @cdx-icon-browser );
-}
-
-.popups-icon--preview-disambiguation {
-	.cdx-mixin-css-icon( @cdx-icon-articles );
-}
-
-// Don't do any event bubbling on childs like <a><span>[</span>2]</a>
-// see https://phabricator.wikimedia.org/T214693
-#mw-content-text .reference a[ href*='#' ] * {
-	pointer-events: none;
-}
-.mwe-popups.mwe-popups-type-reference .mwe-popups-container {
-	.mwe-popups-title .popups-icon--reference-note {
-		// There is currently no "reference-note" icon specified in extension.json
-		display: none;
-	}
-
-	.mwe-popups-extract {
-		margin-right: 0;
-		max-height: inherit;
-		.mwe-popups-scroll {
-			// This is how the @previewFooterHeight in popup.less is calculated
-			@marginBottom: @popupPadding + 34px;
-			// Same as @previewPointerHeight in popup.less
-			@pointerHeight: 8px;
-			max-height: 401px - @popupPadding - @marginBottom + @pointerHeight;
-			overflow: auto;
-			padding-right: @popupPadding;
-		}
-
-		.mw-parser-output {
-			overflow-wrap: break-word;
-		}
-
-		// Remove the default fade-out effect set by popup.less
-		&::after {
-			display: none;
-		}
-
-		.mwe-popups-fade {
-			position: absolute;
-			width: 100%;
-			height: @lineHeight;
-			background-color: transparent;
-			background-image: linear-gradient( rgba( 255, 255, 255, 0 ), rgba( 255, 255, 255, 1 ) );
-			opacity: 0;
-			pointer-events: none; // Allows clicking "through" the element
-			transition: opacity 250ms ease;
-		}
-
-		&.mwe-popups-fade-out .mwe-popups-fade {
-			opacity: 1;
-		}
-	}
-	.mwe-collapsible-placeholder {
-		font-weight: bold;
-		margin: 1em 0;
-		position: relative;
-	}
-}
diff --git a/resources/ext.popups.referencePreviews/referencePreviews.js b/resources/ext.popups.referencePreviews/referencePreviews.js
deleted file mode 100644
index ab62159d7..000000000
--- a/resources/ext.popups.referencePreviews/referencePreviews.js
+++ /dev/null
@@ -1,27 +0,0 @@
-let isTracking = false;
-
-const LOGGING_SCHEMA = 'event.ReferencePreviewsPopups';
-
-/**
- * Run once the preview is initialized.
- */
-function initReferencePreviewsInstrumentation() {
-	if ( mw.config.get( 'wgPopupsReferencePreviews' ) &&
-		navigator.sendBeacon &&
-		mw.config.get( 'wgIsArticle' ) &&
-		!isTracking
-	) {
-		isTracking = true;
-		mw.track( LOGGING_SCHEMA, { action: 'pageview' } );
-	}
-}
-
-function isTrackingEnabled() {
-	return isTracking;
-}
-
-module.exports = {
-	LOGGING_SCHEMA,
-	initReferencePreviewsInstrumentation,
-	isTrackingEnabled
-};
diff --git a/resources/ext.popups.referencePreviews/setUserConfigFlags.js b/resources/ext.popups.referencePreviews/setUserConfigFlags.js
deleted file mode 100644
index 25d67215c..000000000
--- a/resources/ext.popups.referencePreviews/setUserConfigFlags.js
+++ /dev/null
@@ -1,29 +0,0 @@
-/**
- * @module setUserConfigFlags
- */
-
-/**
- * Same as in includes/PopupsContext.php
- */
-const REF_TOOLTIPS_ENABLED = 2,
-	REFERENCE_PREVIEWS_ENABLED = 4;
-
-/**
- * Decodes the bitmask that represents preferences to the related config options.
- *
- * @param {mw.Map} config
- */
-module.exports = function setUserConfigFlags( config ) {
-	const popupsFlags = parseInt( config.get( 'wgPopupsFlags' ), 10 );
-
-	/* eslint-disable no-bitwise */
-	config.set(
-		'wgPopupsConflictsWithRefTooltipsGadget',
-		!!( popupsFlags & REF_TOOLTIPS_ENABLED )
-	);
-	config.set(
-		'wgPopupsReferencePreviews',
-		!!( popupsFlags & REFERENCE_PREVIEWS_ENABLED )
-	);
-	/* eslint-enable no-bitwise */
-}