diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8812b772..97856d70 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -41,7 +41,6 @@ jobs:
         run: Build/Scripts/runTests.sh -b docker -p ${{ matrix.php }} -s lint
 
       - name: Phpstan
-        if: ${{ matrix.php <= '8.3' }}
         run: Build/Scripts/runTests.sh -b docker -p ${{ matrix.php }} -s phpstan
 
       - name: Unit Tests
diff --git a/Build/phpstan/phpstan-baseline.neon b/Build/phpstan/phpstan-baseline.neon
index 208a1a5c..a39ba5db 100644
--- a/Build/phpstan/phpstan-baseline.neon
+++ b/Build/phpstan/phpstan-baseline.neon
@@ -35,9 +35,3 @@ parameters:
 			identifier: notIdentical.alwaysTrue
 			count: 1
 			path: ../../Classes/Core/Functional/FunctionalTestCase.php
-
-		-
-			message: '#^Call to function method_exists\(\) with ''TYPO3\\\\CMS\\\\Core\\\\Core\\\\Bootstrap'' and ''loadExtTables'' will always evaluate to true\.$#'
-			identifier: function.alreadyNarrowedType
-			count: 1
-			path: ../../Classes/Core/Testbase.php
diff --git a/Build/phpstan/phpstan.neon b/Build/phpstan/phpstan.neon
index 1f0230a7..62141b2b 100644
--- a/Build/phpstan/phpstan.neon
+++ b/Build/phpstan/phpstan.neon
@@ -15,6 +15,16 @@ parameters:
     - ../../Classes
     - ../../Tests
 
+  ignoreErrors:
+    # Bootstrap::loadExtTables() exists in TYPO3 v14 only. With v14 the check in
+    # Testbase::loadExtensionTables() is always true, with v15 it is necessary.
+    # So PHPStan must not report this entry as unmatched.
+    -
+      message: '#^Call to function method_exists\(\) with ''TYPO3\\\\CMS\\\\Core\\\\Core\\\\Bootstrap'' and ''loadExtTables'' will always evaluate to true\.$#'
+      identifier: function.alreadyNarrowedType
+      path: ../../Classes/Core/Testbase.php
+      reportUnmatched: false
+
   excludePaths:
     # Text fixtures extensions uses $_EXTKEY phpstan would be report as "might not defined"
     - ../../Tests/Unit/*/Fixtures/Extensions/*/ext_emconf.php
diff --git a/Classes/Core/Testbase.php b/Classes/Core/Testbase.php
index 9eb783f9..fd52c0ba 100644
--- a/Classes/Core/Testbase.php
+++ b/Classes/Core/Testbase.php
@@ -934,6 +934,8 @@ private function truncateAllTablesForOtherDatabases(): void
      */
     public function loadExtensionTables(): void
     {
+        // Bootstrap::loadExtTables() exists in TYPO3 v14 only. For PHPStan,
+        // see the ignoreErrors entry in Build/phpstan/phpstan.neon.
         if (method_exists(Bootstrap::class, 'loadExtTables')) {
             Bootstrap::loadExtTables();
         }