diff --git a/chrome/content/zotero/xpcom/reader.js b/chrome/content/zotero/xpcom/reader.js
index 70163d6cc5..7e452d9873 100644
--- a/chrome/content/zotero/xpcom/reader.js
+++ b/chrome/content/zotero/xpcom/reader.js
@@ -825,6 +825,10 @@ class ReaderTab extends ReaderInstance {
 				this._iframeWindow.addEventListener('error', (event) => {
 					Zotero.logError(event.error);
 				});
+
+				this._iframeWindow.wrappedJSObject.zoteroConfirmDeletion = function (plural) {
+					return Services.prompt.confirm(null, '', Zotero.getString('pdfReader.deleteAnnotation.' + (plural ? 'plural' : 'singular')));
+				};
 			}
 		});
 		
diff --git a/chrome/locale/en-US/zotero/zotero.properties b/chrome/locale/en-US/zotero/zotero.properties
index 34b9d10ea4..60fb77b0dd 100644
--- a/chrome/locale/en-US/zotero/zotero.properties
+++ b/chrome/locale/en-US/zotero/zotero.properties
@@ -1376,6 +1376,8 @@ pdfReader.thisPage = This page
 pdfReader.thisPageAndLaterPages = This page and later pages
 pdfReader.allPages = All pages
 pdfReader.autoDetect = Auto-Detect
+pdfReader.deleteAnnotation.singular = Delete the selected annotation?
+pdfReader.deleteAnnotation.plural = Delete selected annotations?
 
 spellCheck.checkSpelling = Check Spelling
 spellCheck.addRemoveDictionaries = Add/Remove Dictionaries…
diff --git a/pdf-reader b/pdf-reader
index b451e53a13..99bd30047e 160000
--- a/pdf-reader
+++ b/pdf-reader
@@ -1 +1 @@
-Subproject commit b451e53a13b918c49da4937cbbdd3d62424dff73
+Subproject commit 99bd30047e866836d91230db64703157dce275f6