diff --git a/CHANGELOG b/CHANGELOG
index 0365a0865..92e60a233 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -7,6 +7,7 @@
  * Track the source offset of each token and expose it via `Token::getOffset()`
  * Fix nested `block()` calls to resolve against the overriding template when a block rendered through `block(name, template)` calls `parent()`
  * Deprecate the possibility to use a `block` tag within a capture node (like `set`)
+ * Deprecate the possibility to use a `block` tag within a capture node (like `set`) in child templates
  * Deprecate using a `macro`, `extends`, or `use` tag outside the root of a template
  * Stop reporting a skipped test in `IntegrationTestCase` when there is no legacy test to run
  * Fix `markdown_to_html` to strip the indentation shared by all lines instead of mangling content that starts with a blank line
diff --git a/doc/deprecated.rst b/doc/deprecated.rst
index 25bc8d5b8..30267cb5b 100644
--- a/doc/deprecated.rst
+++ b/doc/deprecated.rst
@@ -302,9 +302,10 @@ Templates
   instances of ``Twig\TemplateWrapper`` instead.
 
 * Having a "block" definition nested in another node that captures the output
-  (like "set") is deprecated in Twig 3.14 and will throw in Twig 4.0. Such use
-  cases should be avoided as the "block" tag is used to both define the block
-  AND display it in place. Here is how you can decouple both easily:
+  (like "set") in a child template is deprecated in Twig 3.14 and will throw
+  in Twig 4.0. Such use cases should be avoided as the "block" tag is used to
+  both define the block AND display it in place. Here is how you can decouple
+  both:
 
   Before::
 
diff --git a/src/NodeVisitor/CorrectnessNodeVisitor.php b/src/NodeVisitor/CorrectnessNodeVisitor.php
index 0d4400e35..e0afd4d60 100644
--- a/src/NodeVisitor/CorrectnessNodeVisitor.php
+++ b/src/NodeVisitor/CorrectnessNodeVisitor.php
@@ -20,6 +20,7 @@ use Twig\Node\MacroNode;
 use Twig\Node\ModuleNode;
 use Twig\Node\Node;
 use Twig\Node\NodeCaptureInterface;
+use Twig\Node\NodeOutputInterface;
 use Twig\Node\Nodes;
 use Twig\Node\TextNode;
 
@@ -145,6 +146,10 @@ final class CorrectnessNodeVisitor implements NodeVisitorInterface
             return $node->isBlank();
         }
 
+        if (!$node instanceof BlockReferenceNode && $node instanceof NodeOutputInterface) {
+            return false;
+        }
+
         foreach ($node as $n) {
             if (!$this->isEmptyOutputNode($n)) {
                 return false;
diff --git a/src/TokenParser/ExtendsTokenParser.php b/src/TokenParser/ExtendsTokenParser.php
index c1f0d7581..f6d9d0289 100644
--- a/src/TokenParser/ExtendsTokenParser.php
+++ b/src/TokenParser/ExtendsTokenParser.php
@@ -12,6 +12,7 @@
 
 namespace Twig\TokenParser;
 
+use Twig\Error\SyntaxError;
 use Twig\Node\ConfigNode;
 use Twig\Node\Node;
 use Twig\Token;
@@ -27,8 +28,16 @@ final class ExtendsTokenParser extends AbstractTokenParser
 {
     public function parse(Token $token): Node
     {
+        $stream = $this->parser->getStream();
+
+        if ($this->parser->peekBlockStack()) {
+            throw new SyntaxError('Cannot use "extend" in a block.', $token->getLine(), $stream->getSourceContext());
+        } elseif (!$this->parser->isMainScope()) {
+            throw new SyntaxError('Cannot use "extend" in a macro.', $token->getLine(), $stream->getSourceContext());
+        }
+
         $this->parser->setParent($this->parser->parseExpression());
-        $this->parser->getStream()->expect(Token::BLOCK_END_TYPE);
+        $stream->expect(Token::BLOCK_END_TYPE);
 
         return new ConfigNode($token->getLine());
     }
diff --git a/tests/Fixtures/exceptions/child_print_outside_blocks.test b/tests/Fixtures/exceptions/child_print_outside_blocks.test
new file mode 100644
index 000000000..343a92e3e
--- /dev/null
+++ b/tests/Fixtures/exceptions/child_print_outside_blocks.test
@@ -0,0 +1,17 @@
+--TEST--
+Exception for child templates printing content outside blocks defined by parent
+--TEMPLATE--
+{% extends 'base.twig' %}
+
+{{ content }}
+
+{% block sidebar %}
+    Content inside a block.
+{% endblock %}
+--TEMPLATE(base.twig)--
+{% block sidebar %}
+{% endblock %}
+--DATA--
+return ['content' => 'Content outside a block.'];
+--EXCEPTION--
+Twig\Error\SyntaxError: A template that extends another one cannot include content outside Twig blocks. Did you forget to put the content inside a {% block %} tag in "index.twig" at line 4?
diff --git a/tests/Fixtures/tags/inheritance/extends_in_block_after_parent.test b/tests/Fixtures/tags/inheritance/extends_in_block_after_parent.test
new file mode 100644
index 000000000..4c31b092a
--- /dev/null
+++ b/tests/Fixtures/tags/inheritance/extends_in_block_after_parent.test
@@ -0,0 +1,14 @@
+--TEST--
+"extends" tag in a block after a parent has been defined
+--TEMPLATE--
+{% extends "base.twig" %}
+
+{% block foo %}
+    {% extends "foo.twig" %}
+{% endblock %}
+--TEMPLATE(base.twig)--
+--TEMPLATE(foo.twig)--
+--DATA--
+return []
+--EXCEPTION--
+Twig\Error\SyntaxError: Cannot use "extend" in a block in "index.twig" at line 5.
diff --git a/tests/Fixtures/tags/inheritance/extends_in_macro_after_parent.test b/tests/Fixtures/tags/inheritance/extends_in_macro_after_parent.test
new file mode 100644
index 000000000..82ac30c6a
--- /dev/null
+++ b/tests/Fixtures/tags/inheritance/extends_in_macro_after_parent.test
@@ -0,0 +1,14 @@
+--TEST--
+"extends" tag in a macro after a parent has been defined
+--TEMPLATE--
+{% extends "base.twig" %}
+
+{% macro foo() %}
+    {% extends "foo.twig" %}
+{% endmacro %}
+--TEMPLATE(base.twig)--
+--TEMPLATE(foo.twig)--
+--DATA--
+return []
+--EXCEPTION--
+Twig\Error\SyntaxError: Cannot use "extend" in a macro in "index.twig" at line 5.
diff --git a/tests/Node/TextTest.php b/tests/Node/TextTest.php
index 7402da18a..748ded6e4 100644
--- a/tests/Node/TextTest.php
+++ b/tests/Node/TextTest.php
@@ -20,6 +20,7 @@ namespace Twig\Tests\Node;
  * file that was distributed with this source code.
  */
 
+use PHPUnit\Framework\Attributes\DataProvider;
 use Twig\Node\TextNode;
 use Twig\Test\NodeTestCase;
 
@@ -43,6 +44,7 @@ class TextTest extends NodeTestCase
     /**
      * @dataProvider getIsBlankData
      */
+    #[DataProvider('getIsBlankData')]
     public function testIsBlank($blank)
     {
         $this->assertTrue((new TextNode($blank, 1))->isBlank());
diff --git a/tests/NodeVisitor/CorrectnessTest.php b/tests/NodeVisitor/CorrectnessTest.php
index 4b23d6758..75b1b7f3c 100644
--- a/tests/NodeVisitor/CorrectnessTest.php
+++ b/tests/NodeVisitor/CorrectnessTest.php
@@ -11,6 +11,7 @@ namespace Twig\Tests\NodeVisitor;
  * file that was distributed with this source code.
  */
 
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
 use Twig\Environment;
 use Twig\Error\SyntaxError;
@@ -18,9 +19,11 @@ use Twig\Loader\ArrayLoader;
 use Twig\Node\BodyNode;
 use Twig\Node\EmptyNode;
 use Twig\Node\Expression\ConstantExpression;
+use Twig\Node\IncludeNode;
 use Twig\Node\ModuleNode;
 use Twig\Node\Node;
 use Twig\Node\Nodes;
+use Twig\Node\PrintNode;
 use Twig\Node\SetNode;
 use Twig\Node\TextNode;
 use Twig\NodeTraverser;
@@ -32,6 +35,7 @@ class CorrectnessTest extends TestCase
     /**
      * @dataProvider getFilterBodyNodesData
      */
+    #[DataProvider('getFilterBodyNodesData')]
     public function testFilterBodyNodes($input, $expected)
     {
         $this->assertEquals($expected, $this->traverse($input, $expected));
@@ -54,6 +58,7 @@ class CorrectnessTest extends TestCase
     /**
      * @dataProvider getFilterBodyNodesDataThrowsException
      */
+    #[DataProvider('getFilterBodyNodesDataThrowsException')]
     public function testFilterBodyNodesThrowsException($input)
     {
         $this->expectException(SyntaxError::class);
@@ -64,6 +69,8 @@ class CorrectnessTest extends TestCase
     {
         return [
             [new TextNode('foo', 1)],
+            [new PrintNode(new ConstantExpression('foo', 1), 1)],
+            [new IncludeNode(new ConstantExpression('foo', 1), null, false, false, 1)],
             [new Nodes([new Nodes([new TextNode('foo', 1)])])],
         ];
     }
@@ -71,6 +78,7 @@ class CorrectnessTest extends TestCase
     /**
      * @dataProvider getFilterBodyNodesWithBOMData
      */
+    #[DataProvider('getFilterBodyNodesWithBOMData')]
     public function testFilterBodyNodesWithBOM($emptyText)
     {
         $input = new TextNode(\chr(0xEF).\chr(0xBB).\chr(0xBF).$emptyText, 1);