diff --git a/src/Monolog/Handler/ProcessHandler.php b/src/Monolog/Handler/ProcessHandler.php
index 96649aad..2855a9f7 100644
--- a/src/Monolog/Handler/ProcessHandler.php
+++ b/src/Monolog/Handler/ProcessHandler.php
@@ -43,10 +43,10 @@ class ProcessHandler extends AbstractProcessingHandler
      */
     private array $pipes = [];
 
-    private float $timeout;    
+    private float $timeout;
 
     /**
-     * @var array<int, string[]>
+     * @var array<int, list<string>>
      */
     protected const DESCRIPTOR_SPEC = [
         0 => ['pipe', 'r'],  // STDIN is a pipe that the child will read from
diff --git a/src/Monolog/Handler/SlackWebhookHandler.php b/src/Monolog/Handler/SlackWebhookHandler.php
index eac51ccb..f265d80c 100644
--- a/src/Monolog/Handler/SlackWebhookHandler.php
+++ b/src/Monolog/Handler/SlackWebhookHandler.php
@@ -27,6 +27,8 @@ class SlackWebhookHandler extends AbstractProcessingHandler
 {
     /**
      * Slack Webhook token
+     *
+     * @var non-empty-string
      */
     private string $webhookUrl;
 
@@ -36,7 +38,7 @@ class SlackWebhookHandler extends AbstractProcessingHandler
     private SlackRecord $slackRecord;
 
     /**
-     * @param string      $webhookUrl             Slack Webhook URL
+     * @param non-empty-string $webhookUrl             Slack Webhook URL
      * @param string|null $channel                Slack channel (encoded ID or name)
      * @param string|null $username               Name of a bot
      * @param bool        $useAttachment          Whether the message should be added to Slack as attachment (plain text otherwise)
diff --git a/src/Monolog/Handler/StreamHandler.php b/src/Monolog/Handler/StreamHandler.php
index 6153cc28..8d4e3f5d 100644
--- a/src/Monolog/Handler/StreamHandler.php
+++ b/src/Monolog/Handler/StreamHandler.php
@@ -201,6 +201,9 @@ class StreamHandler extends AbstractProcessingHandler
         fwrite($stream, (string) $record->formatted);
     }
 
+    /**
+     * @return true
+     */
     private function customErrorHandler(int $code, string $msg): bool
     {
         $this->errorMessage = preg_replace('{^(fopen|mkdir|fwrite)\(.*?\): }', '', $msg);
diff --git a/tests/Monolog/Formatter/LineFormatterTest.php b/tests/Monolog/Formatter/LineFormatterTest.php
index 37f77dc3..5360d948 100644
--- a/tests/Monolog/Formatter/LineFormatterTest.php
+++ b/tests/Monolog/Formatter/LineFormatterTest.php
@@ -193,9 +193,8 @@ class LineFormatterTest extends MonologTestCase
         });
 
         $message = $formatter->format($this->getRecord(Level::Critical, context: ['exception' => new \RuntimeException('Foo')]));
-        $trace = explode('[stacktrace]', $message, 2)[1];
-        $this->assertStringNotContainsString('#', $trace);
-        $this->assertSame(PHP_EOL . PHP_EOL . '"} []' . PHP_EOL, $trace);
+        $this->assertStringNotContainsString('[stacktrace]', $message);
+        $this->assertStringEndsWith('"} []' . PHP_EOL, $message);
     }
 
     public function testDefFormatWithPreviousException()