diff --git a/web/app.js b/web/app.js
index d75d00691752e..02495a20ad250 100644
--- a/web/app.js
+++ b/web/app.js
@@ -553,10 +553,6 @@ let PDFViewerApplication = {
         support = false;
       }
     }
-    if (support && AppOptions.get('disableFullscreen') === true) {
-      support = false;
-    }
-
     return shadow(this, 'supportsFullscreen', support);
   },
 
diff --git a/web/app_options.js b/web/app_options.js
index 8fdd20a605b76..266c90484213f 100644
--- a/web/app_options.js
+++ b/web/app_options.js
@@ -43,11 +43,6 @@ const defaultOptions = {
     value: '',
     kind: OptionKind.VIEWER,
   },
-  disableFullscreen: {
-    /** @type {boolean} */
-    value: viewerCompatibilityParams.disableFullscreen || false,
-    kind: OptionKind.VIEWER,
-  },
   disableHistory: {
     /** @type {boolean} */
     value: false,
diff --git a/web/viewer_compatibility.js b/web/viewer_compatibility.js
index 2debdc412839e..d73c26834fb5c 100644
--- a/web/viewer_compatibility.js
+++ b/web/viewer_compatibility.js
@@ -18,17 +18,8 @@ if (typeof PDFJSDev === 'undefined' || PDFJSDev.test('GENERIC')) {
   const userAgent =
     (typeof navigator !== 'undefined' && navigator.userAgent) || '';
   const isAndroid = /Android/.test(userAgent);
-  const isIE = /Trident/.test(userAgent);
   const isIOS = /\b(iPad|iPhone|iPod)(?=;)/.test(userAgent);
 
-  // Disable fullscreen support for certain problematic configurations.
-  // Support: IE11+ (when embedded).
-  (function checkFullscreenSupport() {
-    if (isIE && window.parent !== window) {
-      compatibilityParams.disableFullscreen = true;
-    }
-  })();
-
   // Limit canvas size to 5 mega-pixels on mobile.
   // Support: Android, iOS
   (function checkCanvasSizeLimitation() {