diff --git a/.php_cs.dist b/.php_cs.dist
index 9fa9529f..818ae0bd 100644
--- a/.php_cs.dist
+++ b/.php_cs.dist
@@ -103,7 +103,7 @@ return PhpCsFixer\Config::create()
         'phpdoc_inline_tag' => true,
         'phpdoc_no_access' => true,
         'phpdoc_no_alias_tag' => true,
-        'phpdoc_no_empty_return' => true,
+        'phpdoc_no_empty_return' => false,
         'phpdoc_no_package' => true,
         'phpdoc_no_useless_inheritdoc' => true,
         'phpdoc_return_self_reference' => true,
diff --git a/src/Controller/InvoiceController.php b/src/Controller/InvoiceController.php
index 4c4f9840..67ec1114 100644
--- a/src/Controller/InvoiceController.php
+++ b/src/Controller/InvoiceController.php
@@ -370,7 +370,7 @@ final class InvoiceController extends AbstractController
      * @Route(path="/template/{id}/delete", name="admin_invoice_template_delete", methods={"GET", "POST"})
      * @Security("is_granted('manage_invoice_template')")
      */
-    public function deleteTemplate(InvoiceTemplate $template, Request $request): Response
+    public function deleteTemplate(InvoiceTemplate $template): Response
     {
         try {
             $this->templateRepository->removeTemplate($template);
diff --git a/src/DependencyInjection/Configuration.php b/src/DependencyInjection/Configuration.php
index 0a28fa78..cc1bfa48 100644
--- a/src/DependencyInjection/Configuration.php
+++ b/src/DependencyInjection/Configuration.php
@@ -237,7 +237,7 @@ class Configuration implements ConfigurationInterface
                     ->defaultValue([])
                 ->end()
                 ->booleanNode('simple_form')
-                    ->defaultTrue()
+                    ->defaultFalse()
                 ->end()
                 ->scalarNode('number_format')
                     ->defaultValue('{Y}/{cy,3}')
diff --git a/src/Event/MetaDisplayEventInterface.php b/src/Event/MetaDisplayEventInterface.php
index d3beec79..fb63f3d0 100644
--- a/src/Event/MetaDisplayEventInterface.php
+++ b/src/Event/MetaDisplayEventInterface.php
@@ -37,6 +37,7 @@ interface MetaDisplayEventInterface
      * Adds a field that should be displayed.
      *
      * @param MetaTableTypeInterface $meta
+     * @return void
      */
-    public function addField(MetaTableTypeInterface $meta);
+    public function addField(MetaTableTypeInterface $meta) /* : void */;
 }
diff --git a/src/Invoice/Calculator/AbstractMergedCalculator.php b/src/Invoice/Calculator/AbstractMergedCalculator.php
index bdec849f..4a6cfef9 100644
--- a/src/Invoice/Calculator/AbstractMergedCalculator.php
+++ b/src/Invoice/Calculator/AbstractMergedCalculator.php
@@ -29,7 +29,12 @@ abstract class AbstractMergedCalculator extends AbstractCalculator
         $this->mergeInvoiceItems($invoiceItem, $entry);
     }
 
-    protected function mergeInvoiceItems(InvoiceItem $invoiceItem, InvoiceItemInterface $entry)
+    /**
+     * @param InvoiceItem $invoiceItem
+     * @param InvoiceItemInterface $entry
+     * @return void
+     */
+    protected function mergeInvoiceItems(InvoiceItem $invoiceItem, InvoiceItemInterface $entry) /* : void */
     {
         $duration = $invoiceItem->getDuration();
         if (null !== $entry->getDuration()) {
diff --git a/src/Invoice/Calculator/AbstractSumInvoiceCalculator.php b/src/Invoice/Calculator/AbstractSumInvoiceCalculator.php
index d58da6e4..bf7bb17c 100644
--- a/src/Invoice/Calculator/AbstractSumInvoiceCalculator.php
+++ b/src/Invoice/Calculator/AbstractSumInvoiceCalculator.php
@@ -53,7 +53,12 @@ abstract class AbstractSumInvoiceCalculator extends AbstractMergedCalculator imp
         return array_values($invoiceItems);
     }
 
-    protected function mergeSumInvoiceItem(InvoiceItem $invoiceItem, InvoiceItemInterface $entry)
+    /**
+     * @param InvoiceItem $invoiceItem
+     * @param InvoiceItemInterface $entry
+     * @return void
+     */
+    protected function mergeSumInvoiceItem(InvoiceItem $invoiceItem, InvoiceItemInterface $entry) /* : void */
     {
         if (method_exists($this, 'mergeSumTimesheet')) {
             @trigger_error('mergeSumTimesheet() is deprecated and will be removed with 2.0 - use mergeSumInvoiceItem() instead', E_USER_DEPRECATED);
diff --git a/src/Invoice/InvoiceItem.php b/src/Invoice/InvoiceItem.php
index 937cc304..488c6c47 100644
--- a/src/Invoice/InvoiceItem.php
+++ b/src/Invoice/InvoiceItem.php
@@ -13,9 +13,6 @@ use App\Entity\Activity;
 use App\Entity\Project;
 use App\Entity\User;
 
-/**
- * @internal
- */
 final class InvoiceItem
 {
     /**
diff --git a/src/Invoice/InvoiceItemRepositoryInterface.php b/src/Invoice/InvoiceItemRepositoryInterface.php
index aa8d741e..3704ce66 100644
--- a/src/Invoice/InvoiceItemRepositoryInterface.php
+++ b/src/Invoice/InvoiceItemRepositoryInterface.php
@@ -15,8 +15,9 @@ interface InvoiceItemRepositoryInterface
 {
     /**
      * @param InvoiceItemInterface[] $invoiceItems
+     * @return void
      */
-    public function setExported(array $invoiceItems);
+    public function setExported(array $invoiceItems) /* : void */;
 
     /**
      * @param InvoiceQuery $query
diff --git a/src/Plugin/PluginManager.php b/src/Plugin/PluginManager.php
index 5df38062..b58bc019 100644
--- a/src/Plugin/PluginManager.php
+++ b/src/Plugin/PluginManager.php
@@ -94,7 +94,8 @@ class PluginManager
         $json = json_decode(file_get_contents($composer), true);
 
         $reqVersion = $json['extra']['kimai']['require'] ?? 'unknown';
-        $version = $json['extra']['kimai']['version'] ?? 'unknown';
+        // the version field is required if we use composer to install a plugin via var/packages/
+        $version = $json['extra']['kimai']['version'] ?? ($json['version'] ?? 'unknown');
         $description = $json['description'] ?? '';
 
         $homepage = $json['homepage'] ?? Constants::HOMEPAGE . '/store/';
diff --git a/src/Repository/ActivityRateRepository.php b/src/Repository/ActivityRateRepository.php
index faca299a..7213fee6 100644
--- a/src/Repository/ActivityRateRepository.php
+++ b/src/Repository/ActivityRateRepository.php
@@ -14,6 +14,9 @@ use App\Entity\ActivityRate;
 use Doctrine\ORM\EntityRepository;
 use Doctrine\ORM\ORMException;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<ActivityRate>
+ */
 class ActivityRateRepository extends EntityRepository
 {
     public function saveRate(ActivityRate $rate)
diff --git a/src/Repository/ActivityRepository.php b/src/Repository/ActivityRepository.php
index 6a60d085..18e619bd 100644
--- a/src/Repository/ActivityRepository.php
+++ b/src/Repository/ActivityRepository.php
@@ -25,6 +25,9 @@ use Doctrine\ORM\Query;
 use Doctrine\ORM\QueryBuilder;
 use Pagerfanta\Pagerfanta;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<Activity>
+ */
 class ActivityRepository extends EntityRepository
 {
     /**
diff --git a/src/Repository/ConfigurationRepository.php b/src/Repository/ConfigurationRepository.php
index 38d7e804..3d2e4012 100644
--- a/src/Repository/ConfigurationRepository.php
+++ b/src/Repository/ConfigurationRepository.php
@@ -15,6 +15,9 @@ use App\Form\Model\SystemConfiguration;
 use Doctrine\ORM\EntityRepository;
 use Doctrine\ORM\ORMException;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<Configuration>
+ */
 class ConfigurationRepository extends EntityRepository implements ConfigLoaderInterface
 {
     private static $cacheByPrefix = null;
diff --git a/src/Repository/CustomerRateRepository.php b/src/Repository/CustomerRateRepository.php
index 081c56c6..b67df5db 100644
--- a/src/Repository/CustomerRateRepository.php
+++ b/src/Repository/CustomerRateRepository.php
@@ -14,6 +14,9 @@ use App\Entity\CustomerRate;
 use Doctrine\ORM\EntityRepository;
 use Doctrine\ORM\ORMException;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<CustomerRate>
+ */
 class CustomerRateRepository extends EntityRepository
 {
     public function saveRate(CustomerRate $rate)
diff --git a/src/Repository/CustomerRepository.php b/src/Repository/CustomerRepository.php
index ce746505..f3e84b90 100644
--- a/src/Repository/CustomerRepository.php
+++ b/src/Repository/CustomerRepository.php
@@ -27,6 +27,9 @@ use Doctrine\ORM\Query;
 use Doctrine\ORM\QueryBuilder;
 use Pagerfanta\Pagerfanta;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<Customer>
+ */
 class CustomerRepository extends EntityRepository
 {
     /**
diff --git a/src/Repository/InvoiceRepository.php b/src/Repository/InvoiceRepository.php
index 4b097c09..f3b68172 100644
--- a/src/Repository/InvoiceRepository.php
+++ b/src/Repository/InvoiceRepository.php
@@ -20,6 +20,9 @@ use Doctrine\ORM\EntityRepository;
 use Doctrine\ORM\QueryBuilder;
 use Pagerfanta\Pagerfanta;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<Invoice>
+ */
 class InvoiceRepository extends EntityRepository
 {
     public function saveInvoice(Invoice $invoice)
diff --git a/src/Repository/InvoiceTemplateRepository.php b/src/Repository/InvoiceTemplateRepository.php
index 2e5f443b..f5a80dd3 100644
--- a/src/Repository/InvoiceTemplateRepository.php
+++ b/src/Repository/InvoiceTemplateRepository.php
@@ -16,6 +16,9 @@ use Doctrine\ORM\QueryBuilder;
 use Pagerfanta\Adapter\DoctrineORMAdapter;
 use Pagerfanta\Pagerfanta;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<InvoiceTemplate>
+ */
 class InvoiceTemplateRepository extends EntityRepository
 {
     public function hasTemplate(): bool
diff --git a/src/Repository/ProjectRateRepository.php b/src/Repository/ProjectRateRepository.php
index e0083386..6fce44a1 100644
--- a/src/Repository/ProjectRateRepository.php
+++ b/src/Repository/ProjectRateRepository.php
@@ -14,6 +14,9 @@ use App\Entity\ProjectRate;
 use Doctrine\ORM\EntityRepository;
 use Doctrine\ORM\ORMException;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<ProjectRate>
+ */
 class ProjectRateRepository extends EntityRepository
 {
     public function saveRate(ProjectRate $rate)
diff --git a/src/Repository/ProjectRepository.php b/src/Repository/ProjectRepository.php
index 828d6ac2..51c6ccaf 100644
--- a/src/Repository/ProjectRepository.php
+++ b/src/Repository/ProjectRepository.php
@@ -26,6 +26,9 @@ use Doctrine\ORM\Query;
 use Doctrine\ORM\QueryBuilder;
 use Pagerfanta\Pagerfanta;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<Project>
+ */
 class ProjectRepository extends EntityRepository
 {
     /**
diff --git a/src/Repository/RolePermissionRepository.php b/src/Repository/RolePermissionRepository.php
index abd027d5..6ad98df7 100644
--- a/src/Repository/RolePermissionRepository.php
+++ b/src/Repository/RolePermissionRepository.php
@@ -14,6 +14,9 @@ use App\Entity\RolePermission;
 use Doctrine\ORM\AbstractQuery;
 use Doctrine\ORM\EntityRepository;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<RolePermission>
+ */
 class RolePermissionRepository extends EntityRepository
 {
     public function saveRolePermission(RolePermission $permission)
diff --git a/src/Repository/RoleRepository.php b/src/Repository/RoleRepository.php
index 5561cb29..59bb7b0e 100644
--- a/src/Repository/RoleRepository.php
+++ b/src/Repository/RoleRepository.php
@@ -14,6 +14,7 @@ use Doctrine\ORM\EntityRepository;
 use Doctrine\ORM\ORMException;
 
 /**
+ * @extends \Doctrine\ORM\EntityRepository<Role>
  * @method Role[] findAll()
  */
 class RoleRepository extends EntityRepository
diff --git a/src/Repository/TagRepository.php b/src/Repository/TagRepository.php
index d5ef3319..a6955bc7 100644
--- a/src/Repository/TagRepository.php
+++ b/src/Repository/TagRepository.php
@@ -18,6 +18,9 @@ use Doctrine\ORM\QueryBuilder;
 use Pagerfanta\Adapter\DoctrineORMAdapter;
 use Pagerfanta\Pagerfanta;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<Tag>
+ */
 class TagRepository extends EntityRepository
 {
     /**
diff --git a/src/Repository/TeamRepository.php b/src/Repository/TeamRepository.php
index db12e7b1..15e6590f 100644
--- a/src/Repository/TeamRepository.php
+++ b/src/Repository/TeamRepository.php
@@ -21,6 +21,9 @@ use Doctrine\ORM\ORMException;
 use Doctrine\ORM\QueryBuilder;
 use Pagerfanta\Pagerfanta;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<Team>
+ */
 class TeamRepository extends EntityRepository
 {
     public function find($id, $lockMode = null, $lockVersion = null)
diff --git a/src/Repository/TimesheetRepository.php b/src/Repository/TimesheetRepository.php
index 2518053f..0a23b850 100644
--- a/src/Repository/TimesheetRepository.php
+++ b/src/Repository/TimesheetRepository.php
@@ -28,6 +28,9 @@ use Doctrine\ORM\EntityRepository;
 use Doctrine\ORM\QueryBuilder;
 use Pagerfanta\Pagerfanta;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<Timesheet>
+ */
 class TimesheetRepository extends EntityRepository
 {
     public const STATS_QUERY_DURATION = 'duration';
diff --git a/src/Repository/UserRepository.php b/src/Repository/UserRepository.php
index 14f7fda0..08cebe07 100644
--- a/src/Repository/UserRepository.php
+++ b/src/Repository/UserRepository.php
@@ -24,6 +24,9 @@ use Pagerfanta\Adapter\DoctrineORMAdapter;
 use Pagerfanta\Pagerfanta;
 use Symfony\Bridge\Doctrine\Security\User\UserLoaderInterface;
 
+/**
+ * @extends \Doctrine\ORM\EntityRepository<User>
+ */
 class UserRepository extends EntityRepository implements UserLoaderInterface
 {
     public function getById($id): ?User
diff --git a/src/Widget/WidgetRendererInterface.php b/src/Widget/WidgetRendererInterface.php
index 70d9841f..8d532f47 100644
--- a/src/Widget/WidgetRendererInterface.php
+++ b/src/Widget/WidgetRendererInterface.php
@@ -28,7 +28,7 @@ interface WidgetRendererInterface
      * The given $options array overwrites the widgets internal options for this call.
      *
      * @param WidgetInterface $widget
-     * @param array $options
+     * @param array<string, mixed> $options
      * @return string
      */
     public function render(WidgetInterface $widget, array $options = []): string;
diff --git a/tests/DependencyInjection/ConfigurationTest.php b/tests/DependencyInjection/ConfigurationTest.php
index 05e64da8..f7699ac8 100644
--- a/tests/DependencyInjection/ConfigurationTest.php
+++ b/tests/DependencyInjection/ConfigurationTest.php
@@ -295,7 +295,7 @@ class ConfigurationTest extends TestCase
                     0 => 'var/invoices/',
                     1 => 'templates/invoice/renderer/',
                 ],
-                'simple_form' => true,
+                'simple_form' => false,
                 'number_format' => '{Y}/{cy,3}',
             ],
             'export' => [