diff --git a/resources/skins.vector.js/sidebarPersistence.js b/resources/skins.vector.js/sidebarPersistence.js
index d0291310a..8014d017f 100644
--- a/resources/skins.vector.js/sidebarPersistence.js
+++ b/resources/skins.vector.js/sidebarPersistence.js
@@ -11,18 +11,6 @@ var /** @type {MwApi} */api,
 	SIDEBAR_CHECKBOX_ID = 'mw-sidebar-checkbox',
 	SIDEBAR_PREFERENCE_NAME = 'VectorSidebarVisible';
 
-/**
- * Checks if persistent is enabled at current time.
- * When a user is using a browser with a screen resolution of < 1000 it is assumed
- * that it is preferred that the sidebar remains closed across page views, as otherwise
- * it gets in the way of reading. More context at T316191.
- *
- * @return {boolean}
- */
-function isPersistentEnabled() {
-	return window.innerWidth >= 1000;
-}
-
 /**
  * Execute a debounced API request to save the sidebar user preference.
  * The request is meant to fire 1000 milliseconds after the last click on
@@ -58,60 +46,17 @@ function saveSidebarState( checkbox ) {
  */
 function bindSidebarClickEvent( checkbox, button ) {
 	if ( checkbox instanceof HTMLInputElement && button ) {
-		var handler = saveSidebarState( checkbox );
-		checkbox.addEventListener( 'input', function () {
-			if ( isPersistentEnabled() ) {
-				handler();
-			}
-		} );
-	}
-}
-
-/**
- * Collapses the sidebar if screen resolution too small.
- *
- * @param {HTMLInputElement} checkbox
- */
-function collapseSidebar( checkbox ) {
-	if ( checkbox.checked ) {
-		checkbox.checked = false;
-		saveSidebarState( checkbox )();
+		checkbox.addEventListener( 'input', saveSidebarState( checkbox ) );
 	}
 }
 
 function init() {
-	var checkbox = /** @type {HTMLInputElement|null} */ (
-			window.document.getElementById( SIDEBAR_CHECKBOX_ID )
-		),
+	var checkbox = window.document.getElementById( SIDEBAR_CHECKBOX_ID ),
 		button = window.document.getElementById( SIDEBAR_BUTTON_ID );
 
 	if ( mw.config.get( 'wgUserName' ) && !mw.config.get( 'wgVectorDisableSidebarPersistence' ) ) {
 		bindSidebarClickEvent( checkbox, button );
 	}
-
-	// If the user has resized their window, an open sidebar will be taking up lots of space
-	// so we should disable it.
-	// When this happens the user must expand it again manually, to avoid conflicts with multiple
-	// open windows (for example when an editor is viewing 2 articles side by side).
-	if ( checkbox ) {
-		var mediaQuery = window.matchMedia( '(max-width: 1000px)' );
-		var onMediaQueryChange = function ( /** @type {MediaQueryListEvent} */ event ) {
-			if ( event.matches ) {
-				// @ts-ignore we checked it already.
-				collapseSidebar( checkbox );
-			}
-		};
-		if ( mediaQuery.matches ) {
-			collapseSidebar( checkbox );
-		}
-		if ( mediaQuery.addEventListener ) {
-			mediaQuery.addEventListener( 'change', onMediaQueryChange );
-		} else {
-			//  Before Safari 14, MediaQueryList is based on EventTarget,
-			// so you must use addListener() and removeListener() to observe media query lists.
-			mediaQuery.addListener( onMediaQueryChange );
-		}
-	}
 }
 
 module.exports = {