diff --git a/lib/private/App/AppStore/Fetcher/Fetcher.php b/lib/private/App/AppStore/Fetcher/Fetcher.php
index bb39637891..c109bacf13 100644
--- a/lib/private/App/AppStore/Fetcher/Fetcher.php
+++ b/lib/private/App/AppStore/Fetcher/Fetcher.php
@@ -98,12 +98,11 @@ abstract class Fetcher {
 
 		$options = [
 			'timeout' => 10,
+			'headers' => ['Accept-Encoding' => 'gzip'],
 		];
 
 		if ($ETag !== '') {
-			$options['headers'] = [
-				'If-None-Match' => $ETag,
-			];
+			$options['headers']['If-None-Match'] = $ETag;
 		}
 
 		$client = $this->clientService->newClient();
diff --git a/tests/lib/App/AppStore/Fetcher/FetcherBase.php b/tests/lib/App/AppStore/Fetcher/FetcherBase.php
index 2e04f22760..45f3f22b9d 100644
--- a/tests/lib/App/AppStore/Fetcher/FetcherBase.php
+++ b/tests/lib/App/AppStore/Fetcher/FetcherBase.php
@@ -249,7 +249,15 @@ abstract class FetcherBase extends TestCase {
 		$client
 			->expects($this->once())
 			->method('get')
-			->with($this->endpoint)
+			->with(
+				$this->equalTo($this->endpoint),
+				$this->equalTo([
+					'timeout' => 10,
+					'headers' => [
+						'Accept-Encoding' => 'gzip',
+					]
+				])
+			)
 			->willReturn($response);
 		$response
 			->expects($this->once())
@@ -342,7 +350,15 @@ abstract class FetcherBase extends TestCase {
 		$client
 			->expects($this->once())
 			->method('get')
-			->with($this->endpoint)
+			->with(
+				$this->equalTo($this->endpoint),
+				$this->equalTo([
+					'timeout' => 10,
+					'headers' => [
+						'Accept-Encoding' => 'gzip',
+					]
+				])
+			)
 			->willReturn($response);
 		$response
 			->expects($this->once())
@@ -430,7 +446,15 @@ abstract class FetcherBase extends TestCase {
 		$client
 			->expects($this->once())
 			->method('get')
-			->with($this->endpoint)
+			->with(
+				$this->equalTo($this->endpoint),
+				$this->equalTo([
+					'timeout' => 10,
+					'headers' => [
+						'Accept-Encoding' => 'gzip',
+					]
+				])
+			)
 			->willReturn($response);
 		$response
 			->expects($this->once())
@@ -495,7 +519,15 @@ abstract class FetcherBase extends TestCase {
 		$client
 			->expects($this->once())
 			->method('get')
-			->with($this->endpoint)
+			->with(
+				$this->equalTo($this->endpoint),
+				$this->equalTo([
+					'timeout' => 10,
+					'headers' => [
+						'Accept-Encoding' => 'gzip',
+					]
+				])
+			)
 			->willThrowException(new \Exception());
 
 		$this->assertSame([], $this->fetcher->get());
@@ -552,7 +584,8 @@ abstract class FetcherBase extends TestCase {
 				$this->equalTo([
 					'timeout' => 10,
 					'headers' => [
-						'If-None-Match' => '"myETag"'
+						'Accept-Encoding' => 'gzip',
+						'If-None-Match' => '"myETag"',
 					]
 				])
 			)->willReturn($response);
@@ -624,6 +657,7 @@ abstract class FetcherBase extends TestCase {
 				$this->equalTo([
 					'timeout' => 10,
 					'headers' => [
+						'Accept-Encoding' => 'gzip',
 						'If-None-Match' => '"myETag"',
 					]
 				])
@@ -710,6 +744,9 @@ abstract class FetcherBase extends TestCase {
 				$this->equalTo($this->endpoint),
 				$this->equalTo([
 					'timeout' => 10,
+					'headers' => [
+						'Accept-Encoding' => 'gzip',
+					],
 				])
 			)
 			->willReturn($response);