diff --git a/chrome/content/zotero/xpcom/file.js b/chrome/content/zotero/xpcom/file.js
index 231b14a61d..59dc2e9850 100644
--- a/chrome/content/zotero/xpcom/file.js
+++ b/chrome/content/zotero/xpcom/file.js
@@ -894,6 +894,25 @@ Zotero.File = new function(){
 	}
 	
 	
+	/**
+	 * @param {String} file
+	 * @param {String} newFile
+	 * @return {String} - Path of new file
+	 */
+	this.moveToUnique = async function (file, newFile) {
+		var targetDir = OS.Path.dirname(newFile);
+		
+		var newNSIFile = this.pathToFile(newFile);
+		newNSIFile.createUnique(Components.interfaces.nsIFile.NORMAL_FILE_TYPE, 0o644);
+		var newName = newNSIFile.leafName;
+		newNSIFile.remove(null);
+		
+		newFile = OS.Path.join(targetDir, newName);
+		await OS.File.move(file, newFile);
+		return newFile;
+	}
+	
+	
 	this.copyToUnique = function (file, newFile) {
 		file = this.pathToFile(file);
 		newFile = this.pathToFile(newFile);
diff --git a/chrome/content/zotero/xpcom/zotero.js b/chrome/content/zotero/xpcom/zotero.js
index a0947cf36d..4c1471582a 100644
--- a/chrome/content/zotero/xpcom/zotero.js
+++ b/chrome/content/zotero/xpcom/zotero.js
@@ -49,7 +49,6 @@ Services.scriptloader.loadSubScript("resource://zotero/polyfill.js");
 	this.flattenArguments = flattenArguments;
 	this.getAncestorByTagName = getAncestorByTagName;
 	this.randomString = randomString;
-	this.moveToUnique = moveToUnique;
 	this.reinit = reinit; // defined in zotero-service.js
 	
 	// Public properties
@@ -1711,7 +1710,8 @@ Services.scriptloader.loadSubScript("resource://zotero/polyfill.js");
 	}
 	
 	
-	function moveToUnique(file, newFile){
+	this.moveToUnique = function (file, newFile) {
+		Zotero.debug("Zotero.moveToUnique() is deprecated -- use Zotero.File.moveToUnique()", 2);
 		newFile.createUnique(Components.interfaces.nsIFile.NORMAL_FILE_TYPE, 0o644);
 		var newName = newFile.leafName;
 		newFile.remove(null);
diff --git a/test/tests/fileTest.js b/test/tests/fileTest.js
index cb26ae072d..224d83afc7 100644
--- a/test/tests/fileTest.js
+++ b/test/tests/fileTest.js
@@ -158,6 +158,21 @@ describe("Zotero.File", function () {
 	});
 	
 	
+	describe("#moveToUnique", function () {
+		it("should move a file to a unique filename", async function () {
+			var tmpDir = Zotero.getTempDirectory().path;
+			var sourceFile = OS.Path.join(tmpDir, "1");
+			var tmpTargetDir = OS.Path.join(tmpDir, "targetDirectory")
+			var targetFile = OS.Path.join(tmpTargetDir, "file.txt");
+			await OS.File.makeDir(tmpTargetDir);
+			await Zotero.File.putContentsAsync(sourceFile, "");
+			await Zotero.File.putContentsAsync(targetFile, "");
+			var newFile = await Zotero.File.moveToUnique(sourceFile, targetFile);
+			assert.equal(OS.Path.join(tmpTargetDir, 'file-1.txt'), newFile);
+		});
+	});
+	
+	
 	describe("#copyDirectory()", function () {
 		it("should copy all files within a directory", function* () {
 			var tmpDir = Zotero.getTempDirectory().path;