diff --git a/composer.json b/composer.json
index 3a48e6db..28148f20 100644
--- a/composer.json
+++ b/composer.json
@@ -21,7 +21,7 @@
         "aws/aws-sdk-php": "^3.0",
         "doctrine/couchdb": "~1.0@dev",
         "elasticsearch/elasticsearch": "^7 || ^8",
-        "graylog2/gelf-php": "^1.4.2",
+        "graylog2/gelf-php": "^1.4.2 || ^2@dev",
         "guzzlehttp/guzzle": "^7.4",
         "guzzlehttp/psr7": "^2.2",
         "mongodb/mongodb": "^1.8",
diff --git a/doc/02-handlers-formatters-processors.md b/doc/02-handlers-formatters-processors.md
index b799006a..96cef403 100644
--- a/doc/02-handlers-formatters-processors.md
+++ b/doc/02-handlers-formatters-processors.md
@@ -31,7 +31,6 @@
   [`mail()`](http://php.net/manual/en/function.mail.php) function.
 - [_SymfonyMailerHandler_](https://github.com/Seldaek/monolog/blob/main/src/Monolog/Handler/SymfonyMailerHandler.php): Sends emails using a [`symfony/mailer`](https://symfony.com/doc/current/mailer.html) instance.
 - [_PushoverHandler_](https://github.com/Seldaek/monolog/blob/main/src/Monolog/Handler/PushoverHandler.php): Sends mobile notifications via the [Pushover](https://www.pushover.net/) API.
-- [_FlowdockHandler_](https://github.com/Seldaek/monolog/blob/main/src/Monolog/Handler/FlowdockHandler.php): Logs records to a [Flowdock](https://www.flowdock.com/) account.
 - [_SlackWebhookHandler_](https://github.com/Seldaek/monolog/blob/main/src/Monolog/Handler/SlackWebhookHandler.php): Logs records to a [Slack](https://www.slack.com/) account using Slack Webhooks.
 - [_SlackHandler_](https://github.com/Seldaek/monolog/blob/main/src/Monolog/Handler/SlackHandler.php): Logs records to a [Slack](https://www.slack.com/) account using the Slack API (complex setup).
 - [_SendGridHandler_](https://github.com/Seldaek/monolog/blob/main/src/Monolog/Handler/SendGridHandler.php): Sends emails via the SendGrid API.
@@ -152,7 +151,6 @@
 - [_ElasticaFormatter_](https://github.com/Seldaek/monolog/blob/main/src/Monolog/Formatter/ElasticaFormatter.php): Used to format log records into an Elastica\Document object, only useful for the ElasticaHandler.
 - [_ElasticsearchFormatter_](https://github.com/Seldaek/monolog/blob/main/src/Monolog/Formatter/ElasticsearchFormatter.php): Used to add index and type keys to log records, only useful for the ElasticsearchHandler.
 - [_LogglyFormatter_](https://github.com/Seldaek/monolog/blob/main/src/Monolog/Formatter/LogglyFormatter.php): Used to format log records into Loggly messages, only useful for the LogglyHandler.
-- [_FlowdockFormatter_](https://github.com/Seldaek/monolog/blob/main/src/Monolog/Formatter/FlowdockFormatter.php): Used to format log records into Flowdock messages, only useful for the FlowdockHandler.
 - [_MongoDBFormatter_](https://github.com/Seldaek/monolog/blob/main/src/Monolog/Formatter/MongoDBFormatter.php): Converts \DateTime instances to \MongoDate and objects recursively to arrays, only useful with the MongoDBHandler.
 - [_LogmaticFormatter_](https://github.com/Seldaek/monolog/blob/main/src/Monolog/Formatter/LogmaticFormatter.php): Used to format log records to [Logmatic](http://logmatic.io/) messages, only useful for the LogmaticHandler.
 - [_FluentdFormatter_](https://github.com/Seldaek/monolog/blob/main/src/Monolog/Formatter/FluentdFormatter.php): Used to format log records to [Fluentd](https://www.fluentd.org/) logs, only useful with the SocketHandler.
diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index 580b169c..50b1978c 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -28,6 +28,9 @@ parameters:
         # legacy elasticsearch namespace failures
         - '# Elastic\\Elasticsearch\\#'
 
+        # legacy GelfPHP 1.x failures
+        - '# Gelf\\Message::set(Facility|Line|File)\(#'
+
 includes:
     - phpstan-baseline.neon
     - vendor/phpstan/phpstan-strict-rules/rules.neon
diff --git a/src/Monolog/Formatter/FlowdockFormatter.php b/src/Monolog/Formatter/FlowdockFormatter.php
index b8f7be52..c64da7c0 100644
--- a/src/Monolog/Formatter/FlowdockFormatter.php
+++ b/src/Monolog/Formatter/FlowdockFormatter.php
@@ -17,6 +17,7 @@ use Monolog\LogRecord;
  * formats the record to be used in the FlowdockHandler
  *
  * @author Dominik Liebler <liebler.dominik@gmail.com>
+ * @deprecated Since 2.9.0 and 3.3.0, Flowdock was shutdown we will thus drop this handler in Monolog 4
  */
 class FlowdockFormatter implements FormatterInterface
 {
diff --git a/src/Monolog/Formatter/GelfMessageFormatter.php b/src/Monolog/Formatter/GelfMessageFormatter.php
index 33116a26..037f1ba9 100644
--- a/src/Monolog/Formatter/GelfMessageFormatter.php
+++ b/src/Monolog/Formatter/GelfMessageFormatter.php
@@ -110,14 +110,6 @@ class GelfMessageFormatter extends NormalizerFormatter
         if (isset($record->channel)) {
             $message->setAdditional('facility', $record->channel);
         }
-        if (isset($extra['line'])) {
-            $message->setAdditional('line', $extra['line']);
-            unset($extra['line']);
-        }
-        if (isset($extra['file'])) {
-            $message->setAdditional('file', $extra['file']);
-            unset($extra['file']);
-        }
 
         foreach ($extra as $key => $val) {
             $val = is_scalar($val) || null === $val ? $val : $this->toJson($val);
diff --git a/src/Monolog/Handler/FlowdockHandler.php b/src/Monolog/Handler/FlowdockHandler.php
index 13581548..d24bec40 100644
--- a/src/Monolog/Handler/FlowdockHandler.php
+++ b/src/Monolog/Handler/FlowdockHandler.php
@@ -27,6 +27,7 @@ use Monolog\LogRecord;
  *
  * @author Dominik Liebler <liebler.dominik@gmail.com>
  * @see https://www.flowdock.com/api/push
+ * @deprecated Since 2.9.0 and 3.3.0, Flowdock was shutdown we will thus drop this handler in Monolog 4
  */
 class FlowdockHandler extends SocketHandler
 {