Index of pdf fail

php occ fulltextsearch:index

An unhandled exception has been thrown:
Error: Call to a member function getContent() on string in /var/www/owncloud/apps-external/files_fulltextsearch/lib/Service/FilesService.php:719
Stack trace:
#0 /var/www/owncloud/apps-external/files_fulltextsearch/lib/Service/FilesService.php(658): OCA\Files_FullTextSearch\Service\FilesService->updateContentFromFile('*** sensitive p...', Object(OC\Files\Node\File))
#1 /var/www/owncloud/apps-external/files_fulltextsearch/lib/Service/FilesService.php(638): OCA\Files_FullTextSearch\Service\FilesService->updateFilesDocumentFromFile(Object(OCA\Files_FullTextSearch\Model\FilesDocument), Object(OC\Files\Node\File))
#2 /var/www/owncloud/apps-external/files_fulltextsearch/lib/Service/FilesService.php(529): OCA\Files_FullTextSearch\Service\FilesService->updateFilesDocument(Object(OCA\Files_FullTextSearch\Model\FilesDocument))
#3 /var/www/owncloud/apps-external/files_fulltextsearch/lib/Provider/FilesProvider.php(268): OCA\Files_FullTextSearch\Service\FilesService->generateDocument(Object(OCA\Files_FullTextSearch\Model\FilesDocument))
#4 /var/www/owncloud/apps-external/fulltextsearch/lib/Service/IndexService.php(317): OCA\Files_FullTextSearch\Provider\FilesProvider->fillIndexDocument(Object(OCA\Files_FullTextSearch\Model\FilesDocument))
#5 /var/www/owncloud/apps-external/fulltextsearch/lib/Service/IndexService.php(204): OCA\FullTextSearch\Service\IndexService->indexDocuments(Object(OCA\FullTextSearch_Elasticsearch\Platform\ElasticSearchPlatform), Object(OCA\Files_FullTextSearch\Provider\FilesProvider), Array, Object(OCA\FullTextSearch\Model\IndexOptions))
#6 /var/www/owncloud/apps-external/fulltextsearch/lib/Command/Index.php(410): OCA\FullTextSearch\Service\IndexService->indexProviderContentFromUser(Object(OCA\FullTextSearch_Elasticsearch\Platform\ElasticSearchPlatform), Object(OCA\Files_FullTextSearch\Provider\FilesProvider), 'admin', Object(OCA\FullTextSearch\Model\IndexOptions))
#7 /var/www/owncloud/apps-external/fulltextsearch/lib/Command/Index.php(273): OCA\FullTextSearch\Command\Index->indexProvider(Object(OCA\Files_FullTextSearch\Provider\FilesProvider), Object(OCA\FullTextSearch\Model\IndexOptions))
#8 /var/www/owncloud/3rdparty/symfony/console/Command/Command.php(255): OCA\FullTextSearch\Command\Index->execute(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#9 /var/www/owncloud/core/Command/Base.php(169): Symfony\Component\Console\Command\Command->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#10 /var/www/owncloud/3rdparty/symfony/console/Application.php(1000): OC\Core\Command\Base->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#11 /var/www/owncloud/3rdparty/symfony/console/Application.php(271): Symfony\Component\Console\Application->doRunCommand(Object(OCA\FullTextSearch\Command\Index), Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#12 /var/www/owncloud/3rdparty/symfony/console/Application.php(147): Symfony\Component\Console\Application->doRun(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#13 /var/www/owncloud/lib/private/Console/Application.php(215): Symfony\Component\Console\Application->run(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
#14 /var/www/owncloud/console.php(100): OC\Console\Application->run()
#15 /var/www/owncloud/occ(11): require_once('/var/www/ownclo...')

If you need pdf file on witch it's falling, i will send it, but with private channel.

elasticsearch 7.11.0
php 7.3.19-1~deb10u1
nextcloud 20.0.6

Start with the php occ fulltextsearch:index command and inspect FilesService.php around lines 719, 658, and 638, where the stack trace reports the failure. Reproduce it with the affected PDF and verify that indexing completes without the getContent() exception and the file is indexed.