diff --git a/tests/org.eclipse.e4.ui.tests.css.core/.classpath b/tests/org.eclipse.e4.ui.tests.css.core/.classpath
index 427e49b0d47..c9bfedfe9ca 100644
--- a/tests/org.eclipse.e4.ui.tests.css.core/.classpath
+++ b/tests/org.eclipse.e4.ui.tests.css.core/.classpath
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <classpath>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-17">
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21">
 		<attributes>
 			<attribute name="module" value="true"/>
 		</attributes>
diff --git a/tests/org.eclipse.e4.ui.tests.css.core/.settings/org.eclipse.jdt.core.prefs b/tests/org.eclipse.e4.ui.tests.css.core/.settings/org.eclipse.jdt.core.prefs
index 690129c5df8..5d768075c2c 100644
--- a/tests/org.eclipse.e4.ui.tests.css.core/.settings/org.eclipse.jdt.core.prefs
+++ b/tests/org.eclipse.e4.ui.tests.css.core/.settings/org.eclipse.jdt.core.prefs
@@ -7,9 +7,9 @@ org.eclipse.jdt.core.compiler.annotation.nullable=org.eclipse.jdt.annotation.Nul
 org.eclipse.jdt.core.compiler.annotation.nullanalysis=disabled
 org.eclipse.jdt.core.compiler.codegen.inlineJsrBytecode=enabled
 org.eclipse.jdt.core.compiler.codegen.methodParameters=do not generate
-org.eclipse.jdt.core.compiler.codegen.targetPlatform=17
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=21
 org.eclipse.jdt.core.compiler.codegen.unusedLocal=preserve
-org.eclipse.jdt.core.compiler.compliance=17
+org.eclipse.jdt.core.compiler.compliance=21
 org.eclipse.jdt.core.compiler.debug.lineNumber=generate
 org.eclipse.jdt.core.compiler.debug.localVariable=generate
 org.eclipse.jdt.core.compiler.debug.sourceFile=generate
@@ -101,7 +101,7 @@ org.eclipse.jdt.core.compiler.problem.unusedTypeParameter=ignore
 org.eclipse.jdt.core.compiler.problem.unusedWarningToken=warning
 org.eclipse.jdt.core.compiler.problem.varargsArgumentNeedCast=warning
 org.eclipse.jdt.core.compiler.release=enabled
-org.eclipse.jdt.core.compiler.source=17
+org.eclipse.jdt.core.compiler.source=21
 org.eclipse.jdt.core.formatter.align_fields_grouping_blank_lines=2147483647
 org.eclipse.jdt.core.formatter.align_type_members_on_columns=false
 org.eclipse.jdt.core.formatter.alignment_for_additive_operator=16
diff --git a/tests/org.eclipse.e4.ui.tests.css.core/META-INF/MANIFEST.MF b/tests/org.eclipse.e4.ui.tests.css.core/META-INF/MANIFEST.MF
index ed3fab0bc63..95a642165a4 100644
--- a/tests/org.eclipse.e4.ui.tests.css.core/META-INF/MANIFEST.MF
+++ b/tests/org.eclipse.e4.ui.tests.css.core/META-INF/MANIFEST.MF
@@ -8,7 +8,7 @@ Require-Bundle: org.eclipse.core.runtime,
  org.eclipse.e4.ui.css.core,
  org.eclipse.e4.ui.css.swt
 Bundle-ActivationPolicy: lazy
-Bundle-RequiredExecutionEnvironment: JavaSE-17
+Bundle-RequiredExecutionEnvironment: JavaSE-21
 Eclipse-BundleShape: dir
 Export-Package: org.eclipse.e4.ui.tests.css.core;x-internal:=true,
  org.eclipse.e4.ui.tests.css.core.parser;x-internal:=true,