diff --git a/lib/private/Template/JSCombiner.php b/lib/private/Template/JSCombiner.php
index c5adcee685..bc548c22fd 100644
--- a/lib/private/Template/JSCombiner.php
+++ b/lib/private/Template/JSCombiner.php
@@ -104,13 +104,20 @@ class JSCombiner {
 	 * @return bool
 	 */
 	protected function isCached($fileName, ISimpleFolder $folder) {
-		$fileName = str_replace('.json', '.js', $fileName) . '.deps';
+		$fileName = str_replace('.json', '.js', $fileName);
+
+		if (!$folder->fileExists($fileName)) {
+			return false;
+		}
+
+		$fileName = $fileName . '.deps';
 		try {
 			$deps = $this->depsCache->get($folder->getName() . '-' . $fileName);
 			if ($deps === null || $deps === '') {
 				$depFile = $folder->getFile($fileName);
 				$deps = $depFile->getContent();
 			}
+
 			// check again
 			if ($deps === null || $deps === '') {
 				$this->logger->info('JSCombiner: deps file empty: ' . $fileName);
diff --git a/tests/lib/Template/JSCombinerTest.php b/tests/lib/Template/JSCombinerTest.php
index d5f7000e0a..bec88801d6 100644
--- a/tests/lib/Template/JSCombinerTest.php
+++ b/tests/lib/Template/JSCombinerTest.php
@@ -187,6 +187,10 @@ class JSCombinerTest extends \Test\TestCase {
 
 		$fileDeps->expects($this->once())->method('getContent')->willReturn('{}');
 
+		$folder->method('fileExists')
+			->with('combine.js')
+			->willReturn(true);
+
 		$folder->method('getFile')
 			->will($this->returnCallback(function($path) use ($file, $fileDeps) {
 				if ($path === 'combine.js') {
@@ -196,6 +200,7 @@ class JSCombinerTest extends \Test\TestCase {
 				if ($path === 'combine.js.deps') {
 					return $fileDeps;
 				}
+
 				$this->fail();
 			}));
 
@@ -221,6 +226,9 @@ class JSCombinerTest extends \Test\TestCase {
 			->willReturn($folder);
 		$folder->method('getName')
 			->willReturn('awesomeapp');
+		$folder->method('fileExists')
+			->with('combine.js')
+			->willReturn(true);
 
 		$file = $this->createMock(ISimpleFile::class);
 
@@ -263,6 +271,9 @@ class JSCombinerTest extends \Test\TestCase {
 	public function testIsCachedWithNotExistingFile() {
 		$fileName = 'combine.json';
 		$folder = $this->createMock(ISimpleFolder::class);
+		$folder->method('fileExists')
+			->with('combine.js')
+			->willReturn(true);
 		$file = $this->createMock(ISimpleFile::class);
 		$folder->method('getFile')
 			->with('combine.js.deps')
@@ -278,6 +289,9 @@ class JSCombinerTest extends \Test\TestCase {
 	public function testIsCachedWithOlderMtime() {
 		$fileName = 'combine.json';
 		$folder = $this->createMock(ISimpleFolder::class);
+		$folder->method('fileExists')
+			->with('combine.js')
+			->willReturn(true);
 		$file = $this->createMock(ISimpleFile::class);
 		$folder->method('getFile')
 			->with('combine.js.deps')
@@ -293,6 +307,9 @@ class JSCombinerTest extends \Test\TestCase {
 	public function testIsCachedWithoutContent() {
 		$fileName = 'combine.json';
 		$folder = $this->createMock(ISimpleFolder::class);
+		$folder->method('fileExists')
+			->with('combine.js')
+			->willReturn(true);
 		$file = $this->createMock(ISimpleFile::class);
 		$folder->method('getFile')
 			->with('combine.js.deps')