With debugging at Developer level:

Invalid get_string() identifier: 'pluginname' or component 'block_community'. Perhaps you are missing $string['pluginname'] = ''; in /lang/en/block_community.php? line 356 of \lib\classes\string_manager_standard.php: call to debugging() line 7409 of \lib\moodlelib.php: call to core_string_manager_standard->get_string() line 80 of \course\format\topcoll\settings.php: call to get_string() line 137 of \lib\classes\plugininfo\format.php: call to include() line 59 of \admin\settings\plugins.php: call to core\plugininfo\format->load_settings() line 8831 of \lib\adminlib.php: call to require() line 31 of \admin\search.php: call to admin_get_root()

There is no /moodle/blocks/community folder, but the /moodle/lang/en/block_community.php file exists and contains $string['pluginname'].

Same for block_participants.