Fatal Error, twig related

I have been updating to WordPress 5.6 and Podlove Publisher 3.2.2 and lost access to all of my episodes. Activating Publisher produces the following message:

“The plugin generated 227 characters of unexpected output during activation. If you notice “headers already sent” messages, problems with syndication feeds or other issues, try deactivating or removing this plugin.”

More to the point, this is what I get when I try to access any episode page:

“Fatal error: Uncaught TypeError: Argument 1 passed to PodlovePublisher_Vendor\Twig\Source::__construct() must be of the type string, null given, called in /srv/www/radius.philo.at/html/wp-content/plugins/podlove-podcasting-plugin-for-wordpress/lib/template/twig_loader_podlove_database.php on line 22 and defined in /srv/www/radius.philo.at/html/wp-content/plugins/podlove-podcasting-plugin-for-wordpress/vendor-prefixed/twig/twig/src/Source.php:28 Stack trace: #0 /srv/www/radius.philo.at/html/wp-content/plugins/podlove-podcasting-plugin-for-wordpress/lib/template/twig_loader_podlove_database.php(22): PodlovePublisher_Vendor\Twig\Source->__construct(NULL, ‘default’, ‘’) #1 /srv/www/radius.philo.at/html/wp-content/plugins/podlove-podcasting-plugin-for-wordpress/vendor-prefixed/twig/twig/src/Loader/ChainLoader.php(52): Podlove\Template\TwigLoaderPodloveDatabase->getSourceContext(‘default’) #2 /srv/www/radius.philo.at/html/wp-content/plugins/podlove-podcasting-plugin-for-wordpress/vendor-prefixed/twig/twig/src/Environment.php(36 in /srv/www/radius.philo.at/html/wp-content/plugins/podlove-podcasting-plugin-for-wordpress/vendor-prefixed/twig/twig/src/Source.php on line 28”

This happens with all plugins deactivated. Here is my system report; thankful for any help,

Website http://radius.philo.at
PHP Version 7.0.16-1~dotdeb+8.1
WordPress Version 5.6
WordPress Theme GeneratePress v3.0.2
Active Plugins
- Podlove Podcast Publisher v3.2.2
- Podlove Web Player v2.1.0
WordPress Database Charset utf8
WordPress Database Collate
Publisher Version 3.2.2
Web Player Version player_v2
Monolog Version 1
open_basedir ok
curl Version 7.38.0
iconv available
simplexml ok
max_execution_time 600
upload_max_filesize 1000M
memory_limit 50M
disable_functions pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,
permalinks ok (/%year%/%monthnum%/%day%/%postname%/)
podlove_permalinks ok
podcast_settings ok
web_player ok
podlove_cache on

0 errors
0 notices
Nice, Everything looks fine!

Same problem here.

Hey Herbert, do you update the publisher from a 2.X version? You use the web player v2. The podlove developers remove the support of the web player v2 and v3 with the publisher 3.0
Best regards,

Thank you for the clarification. Consequently I am searching for the publisher plugin verson 2.10 and have difficulties finding it. Could you give me a hint? (The isssue is that I cannot presently update my php version so that my web player will work .)

@herbovec you can download all versions from podlove from github (https://github.com/podlove/podlove-publisher/releases?after=3.0-beta21). If you need I can provide you a small screencast about the download location.