diff --git a/common.ant.xml b/common.ant.xml
index 7f8244aea7d..f46245f7deb 100755
--- a/common.ant.xml
+++ b/common.ant.xml
@@ -54,7 +54,7 @@
   <property name="javac.debug" value="true"/>
   <property name="javac.debuglevel" value="lines,vars,source"/>
   <property name="javac.encoding" value="utf-8"/>
-  <property name="javac.release" value="8"/>
+  <property name="javac.release" value="11"/>
   <property name="javac.nowarn" value="true"/>
 
   <!-- javac and errorprone instructions from https://errorprone.info/docs/installation#ant -->
diff --git a/dev/core/src/com/google/gwt/dev/jjs/impl/GwtAstBuilder.java b/dev/core/src/com/google/gwt/dev/jjs/impl/GwtAstBuilder.java
index 354d9cdb65a..6cf609c4f10 100644
--- a/dev/core/src/com/google/gwt/dev/jjs/impl/GwtAstBuilder.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/impl/GwtAstBuilder.java
@@ -547,7 +547,13 @@ public void endVisit(YieldStatement x, BlockScope scope) {
       try {
         SourceInfo info = makeSourceInfo(x);
         JExpression expression = pop(x.expression);
-        push(new JYieldStatement(info, expression));
+        if (x.switchExpression == null) {
+          // This is an implicit 'yield' in a case with an arrow - synthesize a break instead and
+          // wrap with a block so that the child count in JDT and GWT matches.
+          push(new JBlock(info, expression.makeStatement(), new JBreakStatement(info, null)));
+        } else {
+          push(new JYieldStatement(info, expression));
+        }
       } catch (Throwable e) {
         throw translateException(x, e);
       }
diff --git a/dev/core/test/com/google/gwt/dev/javac/GeneratedClassnameFinderTest.java b/dev/core/test/com/google/gwt/dev/javac/GeneratedClassnameFinderTest.java
index 65926826dc2..8a5c6de23f1 100644
--- a/dev/core/test/com/google/gwt/dev/javac/GeneratedClassnameFinderTest.java
+++ b/dev/core/test/com/google/gwt/dev/javac/GeneratedClassnameFinderTest.java
@@ -105,36 +105,39 @@ public void testEnum() {
     assertEquals(0, new EnumTester().getGeneratedClasses().size());
   }
 
+  /**
+   * This test requires a lot of care and feeding to keep track of which version of Java the test
+   * classes were built with, and what the current release version is.
+   */
   public void testJavacWeirdness() {
     List<String> classNames = new JavacWeirdnessTester().getGeneratedClasses();
-    if (classNames.size() == 4) {
-      // javac8:
-      // JavacWeirdnessTester$1
+    if (classNames.size() == 3) {
+      // javac 11 with --release=11:
+      // javac 17 with --release=11:
+      // javac 21 with --release=11:
       // JavacWeirdnessTester$2
       // JavacWeirdnessTester$2Foo
       // JavacWeirdnessTester$3Foo
       assertFalse(classNames.get(0) + " should not contain Foo",
               classNames.get(0).contains("Foo"));
-      assertFalse(classNames.get(1) + " should not contain Foo",
-              classNames.get(1).contains("Foo"));
+      assertTrue(classNames.get(1) + " should contain Foo", classNames.get(1).contains("Foo"));
       assertTrue(classNames.get(2) + " should contain Foo", classNames.get(2).contains("Foo"));
-      assertTrue(classNames.get(3) + " should contain Foo", classNames.get(3).contains("Foo"));
     } else if (classNames.size() == 5) {
-      // javac22:
+      // javac 22 with --release=11:
       // JavacWeirdnessTester$1
       // JavacWeirdnessTester$2
       // JavacWeirdnessTester$1Foo
       // JavacWeirdnessTester$2Foo
       // JavacWeirdnessTester$3Foo
       assertFalse(classNames.get(0) + " should not contain Foo",
-              classNames.get(0).contains("Foo"));
+          classNames.get(0).contains("Foo"));
       assertFalse(classNames.get(1) + " should not contain Foo",
-              classNames.get(1).contains("Foo"));
+          classNames.get(1).contains("Foo"));
       assertTrue(classNames.get(2) + " should contain Foo", classNames.get(2).contains("Foo"));
       assertTrue(classNames.get(3) + " should contain Foo", classNames.get(2).contains("Foo"));
       assertTrue(classNames.get(4) + " should contain Foo", classNames.get(3).contains("Foo"));
     } else {
-      fail("Expected 4 or 5 classes, found " + classNames);
+      fail("Expected 3 classes, found " + classNames);
     }
   }
 
diff --git a/doc/build.xml b/doc/build.xml
index 3d0f89d353b..1b777b094ad 100644
--- a/doc/build.xml
+++ b/doc/build.xml
@@ -144,7 +144,7 @@
                  sourcepath="${gwt.root}/user/super/com/google/gwt/emul:${gwt.root}/dev/core/super/com/google/gwt/dev/jjs/intrinsic"
                  encoding="UTF-8"
                  access="public"
-                 source="${javac.release}"
+                 source="8"
                  packagenames="${JAVA_PKGS}"
                  docletpath="${project.build}/../build_tools/doctool/bin"
                  doclet="com.google.doctool.custom.JavaEmulSummaryDoclet">
diff --git a/user/src/com/google/gwt/junit/JUnitShell.java b/user/src/com/google/gwt/junit/JUnitShell.java
index 53f67a7cb2f..842c1ad9794 100644
--- a/user/src/com/google/gwt/junit/JUnitShell.java
+++ b/user/src/com/google/gwt/junit/JUnitShell.java
@@ -60,6 +60,7 @@
 import com.google.gwt.dev.util.arg.ArgHandlerScriptStyle;
 import com.google.gwt.dev.util.arg.ArgHandlerSetProperties;
 import com.google.gwt.dev.util.arg.ArgHandlerSourceLevel;
+import com.google.gwt.dev.util.arg.ArgHandlerStrict;
 import com.google.gwt.dev.util.arg.ArgHandlerWarDir;
 import com.google.gwt.dev.util.arg.ArgHandlerWorkDirOptional;
 import com.google.gwt.junit.JUnitMessageQueue.ClientStatus;
@@ -299,6 +300,7 @@ public int handle(String[] args, int tagIndex) {
       registerHandler(new ArgHandlerFilterJsInteropExports(options));
       registerHandler(new ArgHandlerSetProperties(options));
       registerHandler(new ArgHandlerClosureFormattedOutput(options));
+      registerHandler(new ArgHandlerStrict(options));
 
       /*
        * ----- Options specific to JUnitShell -----
diff --git a/user/src/com/google/gwt/uibinder/attributeparsers/FieldReferenceConverter.java b/user/src/com/google/gwt/uibinder/attributeparsers/FieldReferenceConverter.java
index 7902374e3f6..98d13ccb17e 100644
--- a/user/src/com/google/gwt/uibinder/attributeparsers/FieldReferenceConverter.java
+++ b/user/src/com/google/gwt/uibinder/attributeparsers/FieldReferenceConverter.java
@@ -65,7 +65,7 @@ public static class IllegalFieldReferenceException extends RuntimeException {
   interface Delegate {
     /**
      * Returns the types any parsed field references are expected to return.
-     * Multiple values indicates an overload. E.g., in <a href={...}> either a
+     * Multiple values indicates an overload. E.g., in <code>&lt;a href={...}&gt;</code> either a
      * String or a SafeUri is allowed.
      */
     JType[] getTypes();
diff --git a/user/src/com/google/gwt/user/client/Window.java b/user/src/com/google/gwt/user/client/Window.java
index 972f16d3107..1ec68214daa 100644
--- a/user/src/com/google/gwt/user/client/Window.java
+++ b/user/src/com/google/gwt/user/client/Window.java
@@ -853,7 +853,7 @@ static void onClosed() {
   }
 
   static String onClosing() {
-    if (closeHandlersInitialized) {
+    if (beforeCloseHandlersInitialized) {
       Window.ClosingEvent event = new Window.ClosingEvent();
       fireEvent(event);
       return event.getMessage();
diff --git a/user/test-super/com/google/gwt/dev/jjs/super/com/google/gwt/dev/jjs/test/Java17Test.java b/user/test-super/com/google/gwt/dev/jjs/super/com/google/gwt/dev/jjs/test/Java17Test.java
index fc238a981b6..90960b0a115 100644
--- a/user/test-super/com/google/gwt/dev/jjs/super/com/google/gwt/dev/jjs/test/Java17Test.java
+++ b/user/test-super/com/google/gwt/dev/jjs/super/com/google/gwt/dev/jjs/test/Java17Test.java
@@ -494,4 +494,50 @@ public void testInlinedStringConstantsInCase() {
     };
     assertEquals(4, value);
   }
+
+  // https://github.com/gwtproject/gwt/issues/10044
+  public void testCaseArrowLabelsVoidExpression() {
+    // Each switch is extracted to its own method to avoid the early return bug.
+    assertEquals("success", arrowWithVoidExpr());
+
+    // Arrow with non-void expr
+    assertEquals("success", arrowWithStringExpr());
+    assertEquals("success", arrowWithIntExpr());
+
+    // Arrow with a statement - doesn't fail as part of this bug. This exists to verify
+    // that JDT won't give us a yield with a statement somehow.
+    assertEquals("success", arrowWithStatement());
+  }
+
+  private static String arrowWithVoidExpr() {
+    switch(0) {
+      case 0 -> assertTrue(true);
+    };
+    return "success";
+  }
+
+  private static String arrowWithStringExpr() {
+    switch(0) {
+      case 0 -> new Object().toString();
+    };
+    return "success";
+  }
+
+  private static String arrowWithIntExpr() {
+    switch(0) {
+      case 0 -> new Object().hashCode();
+    };
+    return "success";
+  }
+
+  private static String arrowWithStatement() {
+    switch(0) {
+      case 0 -> {
+        if (true) {
+          new Object().toString();
+        }
+      }
+    };
+    return "success";
+  }
 }
diff --git a/user/test/com/google/gwt/dev/jjs/test/Java17Test.java b/user/test/com/google/gwt/dev/jjs/test/Java17Test.java
index 39e0253397c..844ff25c38c 100644
--- a/user/test/com/google/gwt/dev/jjs/test/Java17Test.java
+++ b/user/test/com/google/gwt/dev/jjs/test/Java17Test.java
@@ -121,6 +121,9 @@ public void testSwitchExprInlining() {
   public void testInlinedStringConstantsInCase() {
     assertFalse(isGwtSourceLevel17());
   }
+  public void testCaseArrowLabelsVoidExpression() {
+    assertFalse(isGwtSourceLevel17());
+  }
 
   private boolean isGwtSourceLevel17() {
     return JUnitShell.getCompilerOptions().getSourceLevel().compareTo(SourceLevel.JAVA17) >= 0;
diff --git a/user/test/com/google/gwt/junit/JUnitShellTest.java b/user/test/com/google/gwt/junit/JUnitShellTest.java
index e5b8534d6e0..19695aaa89f 100644
--- a/user/test/com/google/gwt/junit/JUnitShellTest.java
+++ b/user/test/com/google/gwt/junit/JUnitShellTest.java
@@ -45,7 +45,7 @@ public void testDefaultModuleUrl() throws Exception {
   public void testArgOptimize() throws Exception {
     parseGoodArgs("-optimize", "8", "-XdisableInlineLiteralParameters",
         "-XdisableRemoveDuplicateFunctions", "-XdisableClusterSimilarFunctions",
-        "-XdisableOrdinalizeEnums", "-XdisableOptimizeDataflow");
+        "-XdisableOrdinalizeEnums", "-XdisableOptimizeDataflow", "-strict");
   }
 
   private void parseGoodArgs(String... argsToUse) {