diff --git a/src/Control/Middleware/CanonicalURLMiddleware.php b/src/Control/Middleware/CanonicalURLMiddleware.php
index feec6e109..66e2a2afe 100644
--- a/src/Control/Middleware/CanonicalURLMiddleware.php
+++ b/src/Control/Middleware/CanonicalURLMiddleware.php
@@ -412,7 +412,10 @@ class CanonicalURLMiddleware implements HTTPMiddleware
         $paths = (array) $this->getEnforceTrailingSlashConfigIgnorePaths();
         if (!empty($paths)) {
             foreach ($paths as $path) {
-                if (str_starts_with(trim($path, '/'), trim($requestPath, '/'))) {
+                if (str_starts_with(
+                    $this->trailingSlashForComparison($requestPath),
+                    $this->trailingSlashForComparison($path)
+                )) {
                     return false;
                 }
             }
@@ -439,6 +442,15 @@ class CanonicalURLMiddleware implements HTTPMiddleware
         return true;
     }
 
+    /**
+     * Ensure a string has a trailing slash to that we can use str_starts_with and compare
+     * paths like admin/ with administration/ and get a correct result.
+     */
+    private function trailingSlashForComparison(string $path): string
+    {
+        return trim($path, '/') . '/';
+    }
+
     /**
      * @return int
      */
diff --git a/src/Core/Cache/ApcuCacheFactory.php b/src/Core/Cache/ApcuCacheFactory.php
index b41de1603..188224063 100644
--- a/src/Core/Cache/ApcuCacheFactory.php
+++ b/src/Core/Cache/ApcuCacheFactory.php
@@ -3,12 +3,11 @@
 namespace SilverStripe\Core\Cache;
 
 use SilverStripe\Core\Injector\Injector;
-use Symfony\Component\Cache\Simple\ApcuCache;
-use Memcached;
+use Symfony\Component\Cache\Adapter\ApcuAdapter;
+use Symfony\Component\Cache\Psr16Cache;
 
 class ApcuCacheFactory implements CacheFactory
 {
-
     /**
      * @var string
      */
@@ -31,10 +30,11 @@ class ApcuCacheFactory implements CacheFactory
             ? $params['namespace'] . '_' . md5(BASE_PATH)
             : md5(BASE_PATH);
         $defaultLifetime = isset($params['defaultLifetime']) ? $params['defaultLifetime'] : 0;
-        return Injector::inst()->createWithArgs(ApcuCache::class, [
+        $psr6Cache = Injector::inst()->createWithArgs(ApcuAdapter::class, [
             $namespace,
             $defaultLifetime,
             $this->version
         ]);
+        return Injector::inst()->createWithArgs(Psr16Cache::class, [$psr6Cache]);
     }
 }
diff --git a/src/Core/Cache/MemcachedCacheFactory.php b/src/Core/Cache/MemcachedCacheFactory.php
index 307b5e549..1752baf5b 100644
--- a/src/Core/Cache/MemcachedCacheFactory.php
+++ b/src/Core/Cache/MemcachedCacheFactory.php
@@ -3,7 +3,8 @@
 namespace SilverStripe\Core\Cache;
 
 use SilverStripe\Core\Injector\Injector;
-use Symfony\Component\Cache\Simple\MemcachedCache;
+use Symfony\Component\Cache\Adapter\MemcachedAdapter;
+use Symfony\Component\Cache\Psr16Cache;
 use Memcached;
 
 class MemcachedCacheFactory implements CacheFactory
@@ -31,10 +32,11 @@ class MemcachedCacheFactory implements CacheFactory
             ? $params['namespace'] . '_' . md5(BASE_PATH)
             : md5(BASE_PATH);
         $defaultLifetime = isset($params['defaultLifetime']) ? $params['defaultLifetime'] : 0;
-        return Injector::inst()->createWithArgs(MemcachedCache::class, [
+        $psr6Cache = Injector::inst()->createWithArgs(MemcachedAdapter::class, [
             $this->memcachedClient,
             $namespace,
             $defaultLifetime
         ]);
+        return Injector::inst()->createWithArgs(Psr16Cache::class, [$psr6Cache]);
     }
 }
diff --git a/src/Core/CoreKernel.php b/src/Core/CoreKernel.php
index 3af15bb99..db9b69f69 100644
--- a/src/Core/CoreKernel.php
+++ b/src/Core/CoreKernel.php
@@ -6,6 +6,7 @@ use SilverStripe\Control\HTTPResponse_Exception;
 use SilverStripe\Dev\Install\DatabaseAdapterRegistry;
 use SilverStripe\ORM\DB;
 use Exception;
+use LogicException;
 
 /**
  * Simple Kernel container
@@ -112,6 +113,29 @@ class CoreKernel extends BaseKernel
             "password" => Environment::getEnv('SS_DATABASE_PASSWORD') ?: null,
         ];
 
+        // Only add SSL keys in the array if there is an actual value associated with them
+        $sslConf = [
+            'ssl_key' => 'SS_DATABASE_SSL_KEY',
+            'ssl_cert' => 'SS_DATABASE_SSL_CERT',
+            'ssl_ca' => 'SS_DATABASE_SSL_CA',
+            'ssl_cipher' => 'SS_DATABASE_SSL_CIPHER',
+        ];
+        foreach ($sslConf as $key => $envVar) {
+            $envValue = Environment::getEnv($envVar);
+            if ($envValue) {
+                $databaseConfig[$key] = $envValue;
+            }
+        }
+
+        // Having only the key or cert without the other is bad configuration.
+        if ((isset($databaseConfig['ssl_key']) && !isset($databaseConfig['ssl_cert']))
+            || (!isset($databaseConfig['ssl_key']) && isset($databaseConfig['ssl_cert']))
+        ) {
+            user_error('Database SSL cert and key must both be defined to use SSL in the database.', E_USER_WARNING);
+            unset($databaseConfig['ssl_key']);
+            unset($databaseConfig['ssl_cert']);
+        }
+
         // Set the port if called for
         $dbPort = Environment::getEnv('SS_DATABASE_PORT');
         if ($dbPort) {
diff --git a/src/Dev/Install/MySQLDatabaseConfigurationHelper.php b/src/Dev/Install/MySQLDatabaseConfigurationHelper.php
index 1c31fa6cf..21fff8627 100644
--- a/src/Dev/Install/MySQLDatabaseConfigurationHelper.php
+++ b/src/Dev/Install/MySQLDatabaseConfigurationHelper.php
@@ -32,15 +32,15 @@ class MySQLDatabaseConfigurationHelper implements DatabaseConfigurationHelper
                 case 'MySQLDatabase':
                     $conn = mysqli_init();
 
-                    // Set SSL parameters if they exist. All parameters are required.
-                    if (array_key_exists('ssl_key', $databaseConfig) &&
-                        array_key_exists('ssl_cert', $databaseConfig) &&
-                        array_key_exists('ssl_ca', $databaseConfig)
+                    // Set SSL parameters if they exist.
+                    // Must have both the SSL cert and key, or the common authority, or preferably all three.
+                    if ((array_key_exists('ssl_key', $databaseConfig) && array_key_exists('ssl_cert', $databaseConfig))
+                        || array_key_exists('ssl_ca', $databaseConfig)
                     ) {
                         $conn->ssl_set(
-                            $databaseConfig['ssl_key'],
-                            $databaseConfig['ssl_cert'],
-                            $databaseConfig['ssl_ca'],
+                            $databaseConfig['ssl_key'] ?? null,
+                            $databaseConfig['ssl_cert'] ?? null,
+                            $databaseConfig['ssl_ca'] ?? null,
                             dirname($databaseConfig['ssl_ca']),
                             array_key_exists('ssl_cipher', $databaseConfig)
                                 ? $databaseConfig['ssl_cipher']
diff --git a/src/Forms/Form.php b/src/Forms/Form.php
index 5735330b5..96b9d1ee4 100644
--- a/src/Forms/Form.php
+++ b/src/Forms/Form.php
@@ -1617,7 +1617,9 @@ class Form extends ViewableData implements HasRequestHandler
     public function defaultAction()
     {
         if ($this->hasDefaultAction && $this->actions) {
-            return $this->actions->first();
+            return $this->actions->flattenFields()->filterByCallback(function ($field) {
+                return $field instanceof FormAction;
+            })->first();
         }
         return null;
     }
diff --git a/src/Forms/GridField/GridFieldFilterHeader.php b/src/Forms/GridField/GridFieldFilterHeader.php
index 1069b4bdc..b6b71eda5 100755
--- a/src/Forms/GridField/GridFieldFilterHeader.php
+++ b/src/Forms/GridField/GridFieldFilterHeader.php
@@ -6,6 +6,7 @@ use LogicException;
 use SilverStripe\Admin\LeftAndMain;
 use SilverStripe\Control\Controller;
 use SilverStripe\Control\HTTPResponse;
+use SilverStripe\Core\ClassInfo;
 use SilverStripe\Forms\FieldList;
 use SilverStripe\Forms\Form;
 use SilverStripe\Forms\Schema\FormSchema;
@@ -203,20 +204,36 @@ class GridFieldFilterHeader extends AbstractGridFieldComponent implements GridFi
             return false;
         }
         $modelClass = $gridField->getModelClass();
-        // note: searchableFields() will return summary_fields if there are no searchable_fields on the model
-        $searchableFields = array_keys($modelClass::singleton()->searchableFields());
-        $summaryFields = array_keys($modelClass::singleton()->summaryFields());
-        sort($searchableFields);
-        sort($summaryFields);
-        // searchable_fields has been explictily defined i.e. searchableFields() is not falling back to summary_fields
-        if ($searchableFields !== $summaryFields) {
-            return true;
-        }
-        // we have fallen back to summary_fields, check they are filterable
-        foreach ($searchableFields as $searchableField) {
-            if ($list->canFilterBy($searchableField)) {
+        $singleton = singleton($modelClass);
+        if (ClassInfo::hasMethod($singleton, 'summaryFields')
+            && ClassInfo::hasMethod($singleton, 'searchableFields')
+        ) {
+            // note: searchableFields() will return summary_fields if there are no searchable_fields on the model
+            $searchableFields = array_keys($singleton->searchableFields());
+            $summaryFields = array_keys($singleton->summaryFields());
+            sort($searchableFields);
+            sort($summaryFields);
+            // searchable_fields has been explictily defined i.e. searchableFields() is not falling back to summary_fields
+            if ($searchableFields !== $summaryFields) {
                 return true;
             }
+            // we have fallen back to summary_fields, check they are filterable
+            foreach ($searchableFields as $searchableField) {
+                if ($list->canFilterBy($searchableField)) {
+                    return true;
+                }
+            }
+        } else {
+            // Allows non-DataObject classes to be used with this component
+            $columns = $gridField->getColumns();
+            foreach ($columns as $columnField) {
+                $metadata = $gridField->getColumnMetadata($columnField);
+                $title = $metadata['title'];
+
+                if ($title && $list->canFilterBy($columnField)) {
+                    return true;
+                }
+            }
         }
         return false;
     }
diff --git a/src/ORM/Connect/MySQLiConnector.php b/src/ORM/Connect/MySQLiConnector.php
index b4ab7b697..20a45d97c 100644
--- a/src/ORM/Connect/MySQLiConnector.php
+++ b/src/ORM/Connect/MySQLiConnector.php
@@ -96,14 +96,15 @@ class MySQLiConnector extends DBConnector
             );
         }
 
-        // Set SSL parameters if they exist. All parameters are required.
-        if (array_key_exists('ssl_key', $parameters ?? []) &&
-            array_key_exists('ssl_cert', $parameters ?? []) &&
-            array_key_exists('ssl_ca', $parameters ?? [])) {
+        // Set SSL parameters if they exist.
+        // Must have both the SSL cert and key, or the common authority, or preferably all three.
+        if ((array_key_exists('ssl_key', $parameters ?? []) && array_key_exists('ssl_cert', $parameters ?? []))
+            || array_key_exists('ssl_ca', $parameters ?? [])
+        ) {
             $this->dbConn->ssl_set(
-                $parameters['ssl_key'],
-                $parameters['ssl_cert'],
-                $parameters['ssl_ca'],
+                $parameters['ssl_key'] ?? null,
+                $parameters['ssl_cert'] ?? null,
+                $parameters['ssl_ca'] ?? null,
                 dirname($parameters['ssl_ca'] ?? ''),
                 array_key_exists('ssl_cipher', $parameters ?? [])
                     ? $parameters['ssl_cipher']
diff --git a/src/View/SSViewer_BasicIteratorSupport.php b/src/View/SSViewer_BasicIteratorSupport.php
index 04dcaa8e8..074c8d71d 100644
--- a/src/View/SSViewer_BasicIteratorSupport.php
+++ b/src/View/SSViewer_BasicIteratorSupport.php
@@ -26,8 +26,6 @@ class SSViewer_BasicIteratorSupport implements TemplateIteratorProvider
         return [
             'IsFirst',
             'IsLast',
-            'First',
-            'Last',
             'FirstLast',
             'Middle',
             'MiddleString',
diff --git a/tests/php/Control/Middleware/CanonicalURLMiddlewareTest.php b/tests/php/Control/Middleware/CanonicalURLMiddlewareTest.php
index 0798ca594..5689fb767 100644
--- a/tests/php/Control/Middleware/CanonicalURLMiddlewareTest.php
+++ b/tests/php/Control/Middleware/CanonicalURLMiddlewareTest.php
@@ -85,86 +85,114 @@ class CanonicalURLMiddlewareTest extends SapphireTest
         $this->assertFalse($middleware->getForceBasicAuthToSSL(), 'Explicitly set is returned');
     }
 
-    public function testRedirectTrailingSlash()
+    public function provideRedirectTrailingSlash()
     {
-        $testScenarios = [
+        $testScenarios = [];
+        foreach ([true, false] as $forceRedirect) {
+            foreach ([true, false] as $addTrailingSlash) {
+                foreach ([true, false] as $requestHasSlash) {
+                    $testScenarios[] = [
+                        $forceRedirect,
+                        $addTrailingSlash,
+                        $requestHasSlash,
+                    ];
+                }
+            }
+        }
+        return $testScenarios;
+    }
+
+    /**
+     * @dataProvider provideRedirectTrailingSlash
+     */
+    public function testRedirectTrailingSlash(bool $forceRedirect, bool $addTrailingSlash, bool $requestHasSlash)
+    {
+        Controller::config()->set('add_trailing_slash', $addTrailingSlash);
+
+        $noRedirect = !$forceRedirect || ($addTrailingSlash && $requestHasSlash) || (!$addTrailingSlash && !$requestHasSlash);
+        $middleware = $this->getMockedMiddleware(false);
+        $middleware->setEnforceTrailingSlashConfig($forceRedirect);
+
+        $requestSlash = $requestHasSlash ? '/' : '';
+        $requestURL = "/about-us{$requestSlash}";
+
+        $this->performRedirectTest($requestURL, $middleware, !$noRedirect, $addTrailingSlash);
+    }
+
+    private function performRedirectTest(string $requestURL, CanonicalURLMiddleware $middleware, bool $shouldRedirect, bool $addTrailingSlash)
+    {
+        Environment::setEnv('REQUEST_URI', $requestURL);
+        $request = new HTTPRequest('GET', $requestURL);
+        $request->setScheme('https');
+        $request->addHeader('host', 'www.example.com');
+        $mockResponse = (new HTTPResponse)
+            ->setStatusCode(200);
+
+        $result = $middleware->process($request, function () use ($mockResponse) {
+            return $mockResponse;
+        });
+
+        if (!$shouldRedirect) {
+            $this->assertNull($result->getHeader('Location'), 'No location header should be added');
+            $this->assertEquals(200, $result->getStatusCode(), 'No redirection should be made');
+        } else {
+            $this->assertEquals(301, $result->getStatusCode(), 'Responses should be redirected to include/omit trailing slash');
+            if ($addTrailingSlash) {
+                $this->assertStringEndsWith('/', $result->getHeader('Location'), 'Trailing slash should be added');
+            } else {
+                $this->assertStringEndsNotWith('/', $result->getHeader('Location'), 'Trailing slash should be removed');
+            }
+        }
+    }
+
+    public function provideRedirectTrailingSlashIgnorePaths()
+    {
+        return [
             [
-                'forceRedirect' => true,
-                'addTrailingSlash' => true,
-                'requestHasSlash' => true,
-            ],
-            [
-                'forceRedirect' => true,
-                'addTrailingSlash' => true,
-                'requestHasSlash' => false,
-            ],
-            [
-                'forceRedirect' => true,
-                'addTrailingSlash' => false,
-                'requestHasSlash' => true,
-            ],
-            [
-                'forceRedirect' => true,
                 'addTrailingSlash' => false,
                 'requestHasSlash' => false,
             ],
             [
-                'forceRedirect' => false,
-                'addTrailingSlash' => true,
-                'requestHasSlash' => true,
-            ],
-            [
-                'forceRedirect' => false,
-                'addTrailingSlash' => true,
-                'requestHasSlash' => false,
-            ],
-            [
-                'forceRedirect' => false,
                 'addTrailingSlash' => false,
                 'requestHasSlash' => true,
             ],
             [
-                'forceRedirect' => false,
-                'addTrailingSlash' => false,
+                'addTrailingSlash' => true,
+                'requestHasSlash' => true,
+            ],
+            [
+                'addTrailingSlash' => true,
                 'requestHasSlash' => false,
             ],
         ];
-        foreach ($testScenarios as $scenario) {
-            $forceRedirect = $scenario['forceRedirect'];
-            $addTrailingSlash = $scenario['addTrailingSlash'];
-            $requestHasSlash = $scenario['requestHasSlash'];
+    }
 
-            $middleware = $this->getMockedMiddleware(false);
+    /**
+     * @dataProvider provideRedirectTrailingSlashIgnorePaths
+     */
+    public function testRedirectTrailingSlashIgnorePaths(bool $addTrailingSlash, bool $requestHasSlash)
+    {
+        Controller::config()->set('add_trailing_slash', $addTrailingSlash);
 
-            $middleware->setEnforceTrailingSlashConfig($forceRedirect);
-            Controller::config()->set('add_trailing_slash', $addTrailingSlash);
+        $middleware = $this->getMockedMiddleware(false);
+        $middleware->setEnforceTrailingSlashConfig(true);
 
-            $requestSlash = $requestHasSlash ? '/' : '';
-            $requestURL = "/about-us{$requestSlash}";
+        $requestSlash = $requestHasSlash ? '/' : '';
+        $noRedirectPaths = [
+            "/admin{$requestSlash}",
+            "/admin/graphql{$requestSlash}",
+            "/dev/tasks/my-task{$requestSlash}",
+        ];
+        $allowRedirectPaths = [
+            "/administration{$requestSlash}",
+            "/administration/more-path{$requestSlash}",
+        ];
 
-            Environment::setEnv('REQUEST_URI', $requestURL);
-            $request = new HTTPRequest('GET', $requestURL);
-            $request->setScheme('https');
-            $request->addHeader('host', 'www.example.com');
-            $mockResponse = (new HTTPResponse)
-                ->setStatusCode(200);
-
-            $result = $middleware->process($request, function () use ($mockResponse) {
-                return $mockResponse;
-            });
-
-            $noRedirect = !$forceRedirect || ($addTrailingSlash && $requestHasSlash) || (!$addTrailingSlash && !$requestHasSlash);
-            if ($noRedirect) {
-                $this->assertNull($result->getHeader('Location'), 'No location header should be added');
-                $this->assertEquals(200, $result->getStatusCode(), 'No redirection should be made');
-            } else {
-                $this->assertEquals(301, $result->getStatusCode(), 'Responses should be redirected to include/omit trailing slash');
-                if ($addTrailingSlash) {
-                    $this->assertStringEndsWith('/', $result->getHeader('Location'), 'Trailing slash should be added');
-                } else {
-                    $this->assertStringEndsNotWith('/', $result->getHeader('Location'), 'Trailing slash should be removed');
-                }
-            }
+        foreach ($noRedirectPaths as $path) {
+            $this->performRedirectTest($path, $middleware, false, $addTrailingSlash);
+        }
+        foreach ($allowRedirectPaths as $path) {
+            $this->performRedirectTest($path, $middleware, $addTrailingSlash !== $requestHasSlash, $addTrailingSlash);
         }
     }
 
diff --git a/tests/php/Core/Cache/CacheTest.php b/tests/php/Core/Cache/CacheTest.php
index 1853acf88..228b1121a 100644
--- a/tests/php/Core/Cache/CacheTest.php
+++ b/tests/php/Core/Cache/CacheTest.php
@@ -2,14 +2,17 @@
 
 namespace SilverStripe\Core\Tests\Cache;
 
+use Behat\Gherkin\Cache\MemoryCache;
 use Psr\SimpleCache\CacheInterface;
 use SilverStripe\Core\Cache\ApcuCacheFactory;
 use SilverStripe\Core\Cache\MemcachedCacheFactory;
 use SilverStripe\Core\Injector\Injector;
 use SilverStripe\Core\Tests\Cache\CacheTest\MockCache;
 use SilverStripe\Dev\SapphireTest;
-use Symfony\Component\Cache\Simple\ApcuCache;
-use Symfony\Component\Cache\Simple\MemcachedCache;
+use Symfony\Component\Cache\Psr16Cache;
+use Symfony\Component\Cache\Adapter\ApcuAdapter;
+use Symfony\Component\Cache\Adapter\MemcachedAdapter;
+use Memcached;
 
 class CacheTest extends SapphireTest
 {
@@ -22,7 +25,10 @@ class CacheTest extends SapphireTest
                 ApcuCacheFactory::class => [
                     'constructor' => [ 'version' => 'ss40test' ]
                 ],
-                MemcachedCacheFactory::class => MemcachedCacheFactory::class,
+                'MemcachedClient' => Memcached::class,
+                MemcachedCacheFactory::class => [
+                    'constructor' => [ 'memcachedClient' => '%$MemcachedClient' ]
+                ],
                 CacheInterface::class . '.TestApcuCache' =>  [
                     'factory' => ApcuCacheFactory::class,
                     'constructor' => [
@@ -37,42 +43,42 @@ class CacheTest extends SapphireTest
                         'defaultLifetime' => 5600,
                     ],
                 ],
-                ApcuCache::class => MockCache::class,
-                MemcachedCache::class => MockCache::class,
+                Psr16Cache::class => MockCache::class,
+                ApcuAdapter::class => MockCache::class,
+                MemcachedAdapter::class => MockCache::class,
             ]);
     }
 
     public function testApcuCacheFactory()
     {
-        $cache = Injector::inst()->get(CacheInterface::class . '.TestApcuCache');
-        $this->assertInstanceOf(
-            MockCache::class,
-            $cache
-        );
+        $psr16Cache = Injector::inst()->get(CacheInterface::class . '.TestApcuCache');
+        $this->assertInstanceOf(MockCache::class, $psr16Cache);
+        $this->assertEquals(MockCache::class, get_class($psr16Cache->getArgs()[0]));
         $this->assertEquals(
             [
                 'TestApcuCache_' . md5(BASE_PATH),
                 2600,
                 'ss40test'
             ],
-            $cache->getArgs()
+            $psr16Cache->getArgs()[0]->getArgs()
         );
     }
 
     public function testMemCacheFactory()
     {
-        $cache = Injector::inst()->get(CacheInterface::class . '.TestMemcache');
-        $this->assertInstanceOf(
-            MockCache::class,
-            $cache
-        );
+        if (!class_exists(Memcached::class)) {
+            $this->markTestSkipped('Memcached is not installed');
+        }
+        $psr16Cache = Injector::inst()->get(CacheInterface::class . '.TestMemcache');
+        $this->assertInstanceOf(MockCache::class, $psr16Cache);
+        $this->assertEquals(MockCache::class, get_class($psr16Cache->getArgs()[0]));
         $this->assertEquals(
             [
-                null,
+                new MemCached(),
                 'TestMemCache_' . md5(BASE_PATH),
                 5600
             ],
-            $cache->getArgs()
+            $psr16Cache->getArgs()[0]->getArgs()
         );
     }
 }
diff --git a/tests/php/Forms/FormTest.php b/tests/php/Forms/FormTest.php
index e78413a29..eab888d68 100644
--- a/tests/php/Forms/FormTest.php
+++ b/tests/php/Forms/FormTest.php
@@ -7,6 +7,7 @@ use SilverStripe\Control\HTTPRequest;
 use SilverStripe\Control\Session;
 use SilverStripe\Dev\CSSContentParser;
 use SilverStripe\Dev\FunctionalTest;
+use SilverStripe\Forms\CompositeField;
 use SilverStripe\Forms\DateField;
 use SilverStripe\Forms\DatetimeField;
 use SilverStripe\Forms\FieldList;
@@ -23,7 +24,6 @@ use SilverStripe\Forms\Tests\FormTest\ControllerWithStrictPostCheck;
 use SilverStripe\Forms\Tests\FormTest\Player;
 use SilverStripe\Forms\Tests\FormTest\Team;
 use SilverStripe\Forms\Tests\FormTest\TestController;
-use SilverStripe\Forms\Tests\ValidatorTest\TestValidator;
 use SilverStripe\Forms\TextareaField;
 use SilverStripe\Forms\TextField;
 use SilverStripe\Forms\TimeField;
@@ -345,6 +345,23 @@ class FormTest extends FunctionalTest
         );
     }
 
+    public function testDefaultAction()
+    {
+        $form = Form::create(Controller::curr(), 'Form', new FieldList(), new FieldList(
+            new FormAction('doForm', 'Form Action')
+        ));
+        $this->assertNotNull($form->defaultAction());
+        $this->assertEquals('action_doForm', $form->defaultAction()->getName());
+
+        $form = Form::create(Controller::curr(), 'AnotherForm', new FieldList(), new FieldList(
+            new CompositeField(
+                new FormAction('doAnotherForm', 'Another Form Action')
+            )
+        ));
+        $this->assertNotNull($form->defaultAction());
+        $this->assertEquals('action_doAnotherForm', $form->defaultAction()->getName());
+    }
+
     public function testLoadDataFromIgnoreFalseish()
     {
         $form = new Form(
diff --git a/tests/php/Forms/GridField/GridFieldFilterHeaderTest.php b/tests/php/Forms/GridField/GridFieldFilterHeaderTest.php
index ffc5c185d..145a87441 100644
--- a/tests/php/Forms/GridField/GridFieldFilterHeaderTest.php
+++ b/tests/php/Forms/GridField/GridFieldFilterHeaderTest.php
@@ -8,13 +8,16 @@ use SilverStripe\Dev\SapphireTest;
 use SilverStripe\Forms\FieldList;
 use SilverStripe\Forms\Form;
 use SilverStripe\Forms\GridField\GridField;
+use SilverStripe\Forms\GridField\GridFieldConfig;
 use SilverStripe\Forms\GridField\GridFieldConfig_RecordEditor;
 use SilverStripe\Forms\GridField\GridFieldFilterHeader;
 use SilverStripe\Forms\Tests\GridField\GridFieldFilterHeaderTest\Cheerleader;
 use SilverStripe\Forms\Tests\GridField\GridFieldFilterHeaderTest\CheerleaderHat;
 use SilverStripe\Forms\Tests\GridField\GridFieldFilterHeaderTest\Mom;
+use SilverStripe\Forms\Tests\GridField\GridFieldFilterHeaderTest\NonDataObject;
 use SilverStripe\Forms\Tests\GridField\GridFieldFilterHeaderTest\Team;
 use SilverStripe\Forms\Tests\GridField\GridFieldFilterHeaderTest\TeamGroup;
+use SilverStripe\ORM\ArrayList;
 use SilverStripe\ORM\DataList;
 use SilverStripe\ORM\DataObject;
 
@@ -173,7 +176,7 @@ class GridFieldFilterHeaderTest extends SapphireTest
     {
         $gridField = $this->gridField;
         $filterHeader = $gridField->getConfig()->getComponentByType(GridFieldFilterHeader::class);
-        
+
         // test that you can filter by something if searchable_fields is not defined
         // silverstripe will scaffold db columns that are in the gridfield to be
         // searchable by default
@@ -194,4 +197,33 @@ class GridFieldFilterHeaderTest extends SapphireTest
         Config::modify()->set(Team::class, 'summary_fields', ['MySummaryField']);
         $this->assertFalse($filterHeader->canFilterAnyColumns($gridField));
     }
+
+    public function testCanFilterAnyColumnsNonDataObject()
+    {
+        $list = new ArrayList([
+            new NonDataObject([]),
+        ]);
+        $config = GridFieldConfig::create()->addComponent(new GridFieldFilterHeader());
+        $gridField = new GridField('testfield', 'testfield', $list, $config);
+        $form = new Form(null, 'Form', new FieldList([$gridField]), new FieldList());
+        /** @var GridFieldFilterHeader $component */
+        $component = $gridField->getConfig()->getComponentByType(GridFieldFilterHeader::class);
+
+        $this->assertFalse($component->canFilterAnyColumns($gridField));
+    }
+
+    public function testRenderHeadersNonDataObject()
+    {
+        $list = new ArrayList([
+            new NonDataObject([]),
+        ]);
+        $config = GridFieldConfig::create()->addComponent(new GridFieldFilterHeader());
+        $gridField = new GridField('testfield', 'testfield', $list, $config);
+        $form = new Form(null, 'Form', new FieldList([$gridField]), new FieldList());
+        /** @var GridFieldFilterHeader $component */
+        $component = $gridField->getConfig()->getComponentByType(GridFieldFilterHeader::class);
+        $htmlFragment = $component->getHTMLFragments($gridField);
+
+        $this->assertNull($htmlFragment);
+    }
 }
diff --git a/tests/php/Forms/GridField/GridFieldFilterHeaderTest/NonDataObject.php b/tests/php/Forms/GridField/GridFieldFilterHeaderTest/NonDataObject.php
new file mode 100644
index 000000000..c446dddfc
--- /dev/null
+++ b/tests/php/Forms/GridField/GridFieldFilterHeaderTest/NonDataObject.php
@@ -0,0 +1,14 @@
+<?php
+
+namespace SilverStripe\Forms\Tests\GridField\GridFieldFilterHeaderTest;
+
+use SilverStripe\Dev\TestOnly;
+use SilverStripe\View\ArrayData;
+
+class NonDataObject extends ArrayData implements TestOnly
+{
+    public function summaryFields()
+    {
+        return ['Title' => 'Title'];
+    }
+}