Call to a member function getText() on string

With the most recent dev version (also for search_api and search_api_solr), I get the following error. It might be a configuration issue (string vs fulltext fields) or the code might depend on different module versions.

The website encountered an unexpected error. Please try again later.
Error: Call to a member function getText() on string in Drupal\search_api_solr\Plugin\search_api\backend\SearchApiSolrBackend->getExcerpt() (line 2203 of modules/contrib/search_api_solr/src/Plugin/search_api/backend/SearchApiSolrBackend.php).
Drupal\search_api_solr\Plugin\search_api\backend\SearchApiSolrBackend->getExcerpt(Array, '83u8st-solr_content-entity:media/10:de', Object, Array) (Line: 1441)
Drupal\search_api_solr\Plugin\search_api\backend\SearchApiSolrBackend->extractResults(Object, Object) (Line: 1016)
Drupal\search_api_solr\Plugin\search_api\backend\SearchApiSolrBackend->search(Object) (Line: 455)
Drupal\search_api\Entity\Server->search(Object) (Line: 493)
Drupal\search_api\Query\Query->execute() (Line: 437)
Drupal\search_api\Plugin\views\query\SearchApiQuery->execute(Object) (Line: 1412)
Drupal\views\ViewExecutable->execute(NULL) (Line: 1440)
Drupal\views\ViewExecutable->render() (Line: 412)
Drupal\rest\Plugin\views\display\RestExport->execute() (Line: 1616)
Drupal\views\ViewExecutable->executeDisplay('rest_export_1', Array) (Line: 78)
Drupal\views\Element\View::preRenderViewElement(Array)
call_user_func(Array, Array) (Line: 376)
Drupal\Core\Render\Renderer->doRender(Array, 1) (Line: 195)
Drupal\Core\Render\Renderer->render(Array, 1) (Line: 139)
Drupal\Core\Render\Renderer->Drupal\Core\Render\{closure}() (Line: 574)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 140)
Drupal\Core\Render\Renderer->renderRoot(Array) (Line: 395)
Drupal\rest\Plugin\views\display\RestExport::buildResponse('search', 'rest_export_1', Array) (Line: 52)
Drupal\views\Routing\ViewPageController->handle('search', 'rest_export_1', Object)
call_user_func_array(Array, Array) (Line: 123)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 574)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 124)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext(Array, Array) (Line: 97)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}()
call_user_func_array(Object, Array) (Line: 144)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 64)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 57)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 47)
Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1) (Line: 99)
Drupal\page_cache\StackMiddleware\PageCache->pass(Object, 1, 1) (Line: 78)
Drupal\page_cache\StackMiddleware\PageCache->handle(Object, 1, 1) (Line: 47)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 50)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 23)
Stack\StackedHttpKernel->handle(Object, 1, 1) (Line: 656)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)