LogicException: The database connection is not serializable.

Problem/Motivation

Error when saving subscriptions on user profile page:

LogicException: The database connection is not serializable. This probably means you are serializing an object that has an indirect reference to the database connection. Adjust your code so that is not necessary. Alternatively, look at DependencySerializationTrait as a temporary solution. in Drupal\Core\Database\Connection->__sleep() (line 1687 of /home2/atwh9578/***/core/lib/Drupal/Core/Database/Connection.php). {"severity_level":3,"@backtrace_string":"#0 [internal function]: Drupal\\Core\\Database\\Connection->__sleep()
#1 /home2/atwh9578/***/modules/contrib/danse/modules/form/src/Payload.php(74): serialize()
#2 /home2/atwh9578/***/modules/contrib/danse/src/PayloadBase.php(35): Drupal\\danse_form\\Payload->prepareArray()
#3 /home2/atwh9578/***/modules/contrib/danse/src/Entity/Event.php(55): Drupal\\danse\\PayloadBase->toArray()
#4 /home2/atwh9578/***/core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php(87): Drupal\\danse\\Entity\\Event::preCreate()
#5 /home2/atwh9578/***/core/lib/Drupal/Core/Entity/ContentEntityBase.php(1143): Drupal\\Core\\Entity\\ContentEntityStorageBase->create()
#6 /home2/atwh9578/***/modules/contrib/danse/src/PluginBase.php(365): Drupal\\Core\\Entity\\ContentEntityBase::create()
#7 /home2/atwh9578/***/modules/contrib/danse/modules/form/src/Plugin/Danse/Form.php(47): Drupal\\danse\\PluginBase->createEvent()
#8 /home2/atwh9578/***/modules/contrib/danse/modules/form/danse_form.module(45): Drupal\\danse_form\\Plugin\\Danse\\Form->createFormEvent()
#9 [internal function]: danse_form_submit_event()
#10 /home2/atwh9578/***/core/lib/Drupal/Core/Form/FormSubmitter.php(114): call_user_func_array()
#11 /home2/atwh9578/***/core/lib/Drupal/Core/Form/FormSubmitter.php(52): Drupal\\Core\\Form\\FormSubmitter->executeSubmitHandlers()
#12 /home2/atwh9578/***/core/lib/Drupal/Core/Form/FormBuilder.php(595): Drupal\\Core\\Form\\FormSubmitter->doSubmitForm()
#13 /home2/atwh9578/***/core/lib/Drupal/Core/Form/FormBuilder.php(323): Drupal\\Core\\Form\\FormBuilder->processForm()
#14 /home2/atwh9578/***/core/lib/Drupal/Core/Controller/FormController.php(73): Drupal\\Core\\Form\\FormBuilder->buildForm()
#15 [internal function]: Drupal\\Core\\Controller\\FormController->getContentResult()
#16 /home2/atwh9578/***/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(123): call_user_func_array()
#17 /home2/atwh9578/***/core/lib/Drupal/Core/Render/Renderer.php(580): Drupal\\Core\\EventSubscriber\\EarlyRenderingControllerWrapperSubscriber->Drupal\\Core\\EventSubscriber\\{closure}()
#18 /home2/atwh9578/***/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(124): Drupal\\Core\\Render\\Renderer->executeInRenderContext()
#19 /home2/atwh9578/***/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(97): Drupal\\Core\\EventSubscriber\\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext()
#20 /home2/atwh9578/***/vendor/symfony/http-kernel/HttpKernel.php(163): Drupal\\Core\\EventSubscriber\\EarlyRenderingControllerWrapperSubscriber->Drupal\\Core\\EventSubscriber\\{closure}()
#21 /home2/atwh9578/***/vendor/symfony/http-kernel/HttpKernel.php(74): Symfony\\Component\\HttpKernel\\HttpKernel->handleRaw()
#22 /home2/atwh9578/***/core/lib/Drupal/Core/StackMiddleware/Session.php(58): Symfony\\Component\\HttpKernel\\HttpKernel->handle()
#23 /home2/atwh9578/***/core/lib/Drupal/Core/StackMiddleware/KernelPreHandle.php(48): Drupal\\Core\\StackMiddleware\\Session->handle()
#24 /home2/atwh9578/***/core/modules/page_cache/src/StackMiddleware/PageCache.php(106): Drupal\\Core\\StackMiddleware\\KernelPreHandle->handle()
#25 /home2/atwh9578/***/core/modules/page_cache/src/StackMiddleware/PageCache.php(85): Drupal\\page_cache\\StackMiddleware\\PageCache->pass()
#26 /home2/atwh9578/***/core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php(48): Drupal\\page_cache\\StackMiddleware\\PageCache->handle()
#27 /home2/atwh9578/***/core/lib/Drupal/Core/StackMiddleware/NegotiationMiddleware.php(51): Drupal\\Core\\StackMiddleware\\ReverseProxyMiddleware->handle()
#28 /home2/atwh9578/***/core/lib/Drupal/Core/StackMiddleware/StackedHttpKernel.php(51): Drupal\\Core\\StackMiddleware\
egotiationMiddleware->handle()
#29 /home2/atwh9578/***/core/lib/Drupal/Core/DrupalKernel.php(686): Drupal\\Core\\StackMiddleware\\StackedHttpKernel->handle()
#30 /home2/atwh9578/***/index.php(19): Drupal\\Core\\DrupalKernel->handle()
#31 {main}","exception":[],"channel":"php","link":"","uid":"1","request_uri":"https://***/fr/user/1/subscriptions","referer":"https://***/fr/user/1/subscriptions","ip":"**.**.**.**","timestamp":1680773426}

Steps to reproduce

- Create a subscription on a content type
- Subscribe to this event on a user profile subscription page

Workarround

You can disable danse_form submodule to avoid this error.

Version

D10.0.7
PHP 8.1.17
DANSE 2.2.15, also tested with 2.2.x-dev