Add json ext as dependency as the core needs this.

composer.json

@@ -29,6 +29,7 @@
     },
     "require": {
         "php": ">=7.2.0",
+        "ext-json": "*",
         "ext-intl": "*",
         "ext-mbstring": "*",
         "aura/intl": "^3.0.0",

src/Cache/Cache.php

@@ -136,8 +136,9 @@ class Cache
      * Finds and builds the instance of the required engine class.
      *
      * @param string $name Name of the config array that needs an engine instance built
-     * @return void
      * @throws \Cake\Cache\InvalidArgumentException When a cache engine cannot be created.
+     * @throws \RuntimeException If loading of the engine failed.
+     * @return void
      */
     protected static function _buildEngine(string $name): void
     {

src/Error/Middleware/ErrorHandlerMiddleware.php

@@ -77,6 +77,7 @@ class ErrorHandlerMiddleware implements MiddlewareInterface
      *
      * @param \Cake\Error\ErrorHandler|array $errorHandler The error handler instance
      *  or config array.
+     * @throws \InvalidArgumentException
      */
     public function __construct($errorHandler = [])
     {

src/ORM/Table.php

@@ -2162,8 +2162,9 @@ class Table implements RepositoryInterface, EventListenerInterface, EventDispatc
     /**
      * @param \Cake\Datasource\EntityInterface[]|\Cake\Datasource\ResultSetInterface $entities Entities to save.
      * @param array|\ArrayAccess|\Cake\ORM\SaveOptionsBuilder $options Options used when calling Table::save() for each entity.
-     * @return \Cake\Datasource\EntityInterface[]|\Cake\Datasource\ResultSetInterface Entities list.
      * @throws \Cake\ORM\Exception\PersistenceFailedException If an entity couldn't be saved.
+     * @throws \Exception If an entity couldn't be saved.
+     * @return \Cake\Datasource\EntityInterface[]|\Cake\Datasource\ResultSetInterface Entities list.
      */
     protected function _saveMany(iterable $entities, $options = []): iterable
     {
@@ -2268,7 +2269,6 @@ class Table implements RepositoryInterface, EventListenerInterface, EventDispatc
      * @param array|\ArrayAccess $options Options used when calling Table::save() for each entity.
      * @return \Cake\Datasource\EntityInterface[]|\Cake\Datasource\ResultSetInterface|false Entities list
      *   on success, false on failure.
-     * @throws \Exception
      * @see \Cake\ORM\Table::delete() for options and events related to this method.
      */
     public function deleteMany(iterable $entities, $options = [])
@@ -2292,7 +2292,6 @@ class Table implements RepositoryInterface, EventListenerInterface, EventDispatc
      * @param \Cake\Datasource\EntityInterface[]|\Cake\Datasource\ResultSetInterface $entities Entities to delete.
      * @param array|\ArrayAccess $options Options used when calling Table::save() for each entity.
      * @return \Cake\Datasource\EntityInterface[]|\Cake\Datasource\ResultSetInterface Entities list.
-     * @throws \Exception
      * @throws \Cake\ORM\Exception\PersistenceFailedException
      * @see \Cake\ORM\Table::delete() for options and events related to this method.
      */