diff --git a/chrome/content/zotero/xpcom/data/notes.js b/chrome/content/zotero/xpcom/data/notes.js
index 19424c36fe..a6f89b2815 100644
--- a/chrome/content/zotero/xpcom/data/notes.js
+++ b/chrome/content/zotero/xpcom/data/notes.js
@@ -145,6 +145,13 @@ Zotero.Notes = new function() {
 		}
 		return doc.body.innerHTML;
 	};
+
+	this.hasSchemaVersion = function (note) {
+		let parser = Components.classes['@mozilla.org/xmlextras/domparser;1']
+		.createInstance(Components.interfaces.nsIDOMParser);
+		let doc = parser.parseFromString(note, 'text/html');
+		return !!doc.querySelector('body > div[data-schema-version]');
+	};
 };
 
 if (typeof process === 'object' && process + '' === '[object process]') {
diff --git a/chrome/content/zotero/xpcom/editorInstance.js b/chrome/content/zotero/xpcom/editorInstance.js
index cb5a23f904..5651505d00 100644
--- a/chrome/content/zotero/xpcom/editorInstance.js
+++ b/chrome/content/zotero/xpcom/editorInstance.js
@@ -88,8 +88,7 @@ class EditorInstance {
 			placeholder: options.placeholder,
 			dir: Zotero.dir,
 			font: this._getFont(),
-			// TODO: We should avoid hitting `data-schema-version` in note text
-			hasBackup: note && note.toLowerCase().indexOf('data-schema-version') < 0
+			hasBackup: note && !Zotero.Notes.hasSchemaVersion(note)
 				|| !!await Zotero.NoteBackups.getNote(this._item.id)
 		});
 	}
diff --git a/chrome/content/zotero/xpcom/noteBackups.js b/chrome/content/zotero/xpcom/noteBackups.js
index ecad1cce51..a38a655eef 100644
--- a/chrome/content/zotero/xpcom/noteBackups.js
+++ b/chrome/content/zotero/xpcom/noteBackups.js
@@ -34,8 +34,7 @@ Zotero.NoteBackups = {
 	
 	ensureBackup: async function(item) {
 		let note = item.note;
-		// TODO: We should avoid hitting `data-schema-version` in note text
-		if (note && note.toLowerCase().indexOf('data-schema-version') < 0) {
+		if (note && !Zotero.Notes.hasSchemaVersion(note)) {
 			await Zotero.DB.queryAsync("INSERT OR IGNORE INTO noteBackups VALUES (?, ?)", [item.id, item.note]);
 		}
 	},