diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
index 52c0f259f7..db96291887 100644
--- a/phpstan-baseline.neon
+++ b/phpstan-baseline.neon
@@ -6075,12 +6075,6 @@ parameters:
 			count: 2
 			path: src/File.php
 
-		-
-			message: '#^Method PhpMyAdmin\\File\:\:getCompression\(\) should return string but returns string\|false\.$#'
-			identifier: return.type
-			count: 1
-			path: src/File.php
-
 		-
 			message: '#^Only booleans are allowed in a negated boolean, resource\|false given\.$#'
 			identifier: booleanNot.exprNotBoolean
@@ -6111,12 +6105,6 @@ parameters:
 			count: 4
 			path: src/File.php
 
-		-
-			message: '#^Switch condition type \(string\) does not match case condition false \(false\)\.$#'
-			identifier: switch.type
-			count: 1
-			path: src/File.php
-
 		-
 			message: '''
 				#^Call to deprecated method getInstance\(\) of class PhpMyAdmin\\Config\:
diff --git a/psalm-baseline.xml b/psalm-baseline.xml
index 588a1d5663..bea15ce1fb 100644
--- a/psalm-baseline.xml
+++ b/psalm-baseline.xml
@@ -4121,9 +4121,6 @@
     <DeprecatedMethod>
       <code><![CDATA[Config::getInstance()]]></code>
     </DeprecatedMethod>
-    <FalsableReturnStatement>
-      <code><![CDATA[$this->compression ?? $this->detectCompression()]]></code>
-    </FalsableReturnStatement>
     <InvalidArrayAccess>
       <code><![CDATA[$_FILES['fields_upload']['error']['multi_edit']]]></code>
     </InvalidArrayAccess>
@@ -4131,9 +4128,6 @@
       <code><![CDATA[$_FILES['fields_upload']['name']['multi_edit']]]></code>
       <code><![CDATA[$_FILES['fields_upload']['tmp_name']['multi_edit']]]></code>
     </InvalidArrayOffset>
-    <InvalidFalsableReturnType>
-      <code><![CDATA[string]]></code>
-    </InvalidFalsableReturnType>
     <InvalidPropertyAssignmentValue>
       <code><![CDATA[$this->handle]]></code>
     </InvalidPropertyAssignmentValue>
diff --git a/src/File.php b/src/File.php
index b764322102..7ff170d165 100644
--- a/src/File.php
+++ b/src/File.php
@@ -400,13 +400,13 @@ final class File
     /**
      * Detects what compression the file uses
      *
-     * @return string|false false on error, otherwise string MIME type of
+     * @return string empty string on error, otherwise string MIME type of
      *                      compression, none for none
      *
      * @todo   move file read part into readChunk() or getChunk()
      * @todo   add support for compression plugins
      */
-    private function detectCompression(): string|false
+    private function detectCompression(): string
     {
         // suppress warnings from being displayed, but not from being logged
         // f.e. any file access outside of open_basedir will issue a warning
@@ -417,7 +417,7 @@ final class File
         if (! $file) {
             $this->errorMessage = Message::error(__('File could not be read!'));
 
-            return false;
+            return '';
         }
 
         $this->compression = Util::getCompressionMimeType($file);
@@ -484,7 +484,7 @@ final class File
         }
 
         switch ($this->getCompression()) {
-            case false:
+            case '':
                 return false;
 
             case 'application/bzip2':