diff --git a/lib/Controller/ChatController.php b/lib/Controller/ChatController.php
index cf931467cd7..3b9c61cec6d 100644
--- a/lib/Controller/ChatController.php
+++ b/lib/Controller/ChatController.php
@@ -880,7 +880,6 @@ public function getObjectsSharedInRoomOverview(int $limit = 7): DataResponse {
 			Attachment::TYPE_VOICE,
 		];
 
-		$messages = [];
 		$messageIdsByType = [];
 		// Get all attachments
 		foreach ($objectTypes as $objectType) {
diff --git a/lib/Controller/ReactionController.php b/lib/Controller/ReactionController.php
index 5d9bbe5317d..466c66b7376 100644
--- a/lib/Controller/ReactionController.php
+++ b/lib/Controller/ReactionController.php
@@ -74,7 +74,7 @@ public function react(int $messageId, string $reaction): DataResponse {
 			return new DataResponse([], Http::STATUS_BAD_REQUEST);
 		}
 		$reactions = $this->reactionManager->retrieveReactionMessages($this->getRoom(), $this->getParticipant(), $messageId);
-		return new DataResponse($reactions, $status);
+		return new DataResponse($this->formatReactions($reactions), $status);
 	}
 
 	#[PublicPage]
@@ -98,7 +98,7 @@ public function delete(int $messageId, string $reaction): DataResponse {
 			return new DataResponse([], Http::STATUS_BAD_REQUEST);
 		}
 
-		return new DataResponse($reactions, Http::STATUS_OK);
+		return new DataResponse($this->formatReactions($reactions), Http::STATUS_OK);
 	}
 
 	#[PublicPage]
@@ -114,6 +114,21 @@ public function getReactions(int $messageId, ?string $reaction): DataResponse {
 
 		$reactions = $this->reactionManager->retrieveReactionMessages($this->getRoom(), $this->getParticipant(), $messageId, $reaction);
 
-		return new DataResponse($reactions, Http::STATUS_OK);
+		return new DataResponse($this->formatReactions($reactions), Http::STATUS_OK);
+	}
+
+
+	/**
+	 * @param array<string, array[]> $reactions
+	 * @return array<string, array[]>|\stdClass
+	 */
+	public function formatReactions(array $reactions): array|\stdClass {
+		if ($this->getResponseFormat() === 'json' && empty($reactions)) {
+			// Cheating here to make sure the reactions array is always a
+			// JSON object on the API, even when there is no reaction at all.
+			return new \stdClass();
+		}
+
+		return $reactions;
 	}
 }
diff --git a/tests/integration/features/bootstrap/FeatureContext.php b/tests/integration/features/bootstrap/FeatureContext.php
index 751390999b3..4d6e4c938ad 100644
--- a/tests/integration/features/bootstrap/FeatureContext.php
+++ b/tests/integration/features/bootstrap/FeatureContext.php
@@ -2262,12 +2262,17 @@ public function userSeesTheFollowingSharedOverviewMediaInRoom($user, $identifier
 		$this->sendRequest('GET', '/apps/spreed/api/' . $apiVersion . '/chat/' . self::$identifierToToken[$identifier] . '/share/overview');
 		$this->assertStatusCode($this->response, $statusCode);
 
-		$overview = $this->getDataFromResponse($this->response);
-		$expected = $formData->getRowsHash();
-		$summarized = array_map(function ($type) {
-			return (string) count($type);
-		}, $overview);
-		Assert::assertEquals($expected, $summarized);
+		$contents = $this->response->getBody()->getContents();
+		$this->assertEmptyArrayIsNotAListButADictionary($formData, $contents);
+		$overview = $this->getDataFromResponseBody($contents);
+
+		if ($formData instanceof TableNode) {
+			$expected = $formData->getRowsHash();
+			$summarized = array_map(function ($type) {
+				return (string) count($type);
+			}, $overview);
+			Assert::assertEquals($expected, $summarized);
+		}
 	}
 
 	/**
@@ -2856,7 +2861,16 @@ public function userCheckCapability($user, $capability, $value) {
 	 * @return array
 	 */
 	protected function getDataFromResponse(ResponseInterface $response) {
-		$jsonBody = json_decode($response->getBody()->getContents(), true);
+		return $this->getDataFromResponseBody($response->getBody()->getContents());
+	}
+
+	/**
+	 * Parses the JSON answer to get the array of users returned.
+	 * @param string $response
+	 * @return array
+	 */
+	protected function getDataFromResponseBody(string $response) {
+		$jsonBody = json_decode($response, true);
 		return $jsonBody['ocs']['data'];
 	}
 
@@ -3322,7 +3336,9 @@ public function userReactWithOnMessageToRoomWith(string $user, string $action, s
 			'reaction' => $reaction
 		]);
 		$this->assertStatusCode($this->response, $statusCode);
-		$this->assertReactionList($formData);
+		if ($statusCode === 200 || $statusCode === 201) {
+			$this->assertReactionList($formData);
+		}
 	}
 
 	/**
@@ -3340,10 +3356,15 @@ public function userRetrieveReactionsOfMessageInRoomWith(string $user, string $r
 	}
 
 	private function assertReactionList(?TableNode $formData): void {
+		$contents = $this->response->getBody()->getContents();
+		$this->assertEmptyArrayIsNotAListButADictionary($formData, $contents);
+		$reactions = $this->getDataFromResponseBody($contents);
+
 		$expected = [];
 		if (!$formData instanceof TableNode) {
 			return;
 		}
+
 		foreach ($formData->getHash() as $row) {
 			$reaction = $row['reaction'];
 			unset($row['reaction']);
@@ -3358,8 +3379,7 @@ private function assertReactionList(?TableNode $formData): void {
 			$expected[$reaction][] = $row;
 		}
 
-		$result = $this->getDataFromResponse($this->response);
-		$result = array_map(static function ($reaction, $list) use ($expected): array {
+		$actual = array_map(static function ($reaction, $list) use ($expected): array {
 			$list = array_map(function ($reaction) {
 				unset($reaction['timestamp']);
 				$reaction['actorId'] = ($reaction['actorType'] === 'guests') ? self::$sessionIdToUser[$reaction['actorId']] : (string) $reaction['actorId'];
@@ -3372,8 +3392,8 @@ private function assertReactionList(?TableNode $formData): void {
 			usort($list, [self::class, 'sortAttendees']);
 			Assert::assertEquals($expected[$reaction], $list, 'Reaction list by type does not match');
 			return $list;
-		}, array_keys($result), array_values($result));
-		Assert::assertCount(count($expected), $result, 'Reaction count does not match');
+		}, array_keys($reactions), array_values($reactions));
+		Assert::assertCount(count($expected), $actual, 'Reaction count does not match');
 	}
 
 	/**
@@ -3791,6 +3811,13 @@ public function setUserStatus(string $user, string $status, int $statusCode, str
 		$this->assertStatusCode($this->response, $statusCode);
 	}
 
+	protected function assertEmptyArrayIsNotAListButADictionary(?TableNode $formData, string $content) {
+		if (!$formData instanceof TableNode || empty($formData->getHash())) {
+			$data = json_decode($content);
+			Assert::assertIsNotArray($data->ocs->data, 'Response ocs.data should be an "object" to represent a JSON dictionary, not a list-array');
+		}
+	}
+
 	/**
 	 * @Then the response error matches with :error
 	 */
diff --git a/tests/integration/features/chat-2/rich-object-share.feature b/tests/integration/features/chat-2/rich-object-share.feature
index e8dcab5ff1f..7158b019e43 100644
--- a/tests/integration/features/chat-2/rich-object-share.feature
+++ b/tests/integration/features/chat-2/rich-object-share.feature
@@ -64,6 +64,7 @@ Feature: chat-2/rich-object-share
     Given user "participant1" creates room "public room" (v4)
       | roomType | 3 |
       | roomName | room |
+    Then user "participant1" sees the following shared summarized overview in room "public room" with 200
     When user "participant1" shares rich-object "call" "R4nd0mT0k3n" '{"name":"Another room","call-type":"group"}' to room "public room" with 201 (v1)
     Then user "participant1" sees the following shared other in room "public room" with 200
       | room        | actorType | actorId      | actorDisplayName         | message  | messageParameters |