First disabled AnyComments – didn’t help.
Now have deleted it – still the same:
Fatal error: Uncaught exception ‘fProgrammerException’ with message ‘The noun specified could not be singularized’ in /var/www/u0674501/data/www/blog.psyalter.ru/wp-content/plugins/wp-testing/vendor/flourish/flourish/fGrammar.php:604 Stack trace: #0 /var/www/u0674501/data/www/blog.psyalter.ru/wp-content/plugins/wp-testing/vendor/flourish/flourish/fORM.php(362): fGrammar::singularize(‘wp4u_anycomment…’) #1 /var/www/u0674501/data/www/blog.psyalter.ru/wp-content/plugins/wp-testing/vendor/flourish/flourish/fActiveRecord.php(2865): fORM::classize(‘wp4u_anycomment…’) #2 /var/www/u0674501/data/www/blog.psyalter.ru/wp-content/plugins/wp-testing/src/Model/Test.php(476): fActiveRecord->store(true) #3 /var/www/u0674501/data/www/blog.psyalter.ru/wp-content/plugins/wp-testing/src/Doer/TestEditor.php(368): WpTesting_Model_Test->storeAll() #4 [internal function]: WpTesting_Doer_TestEditor->saveTest(2611, Object(WP_Post)) #5 /var/www/u0674501/data/www/blog.psyalter.ru/wp-includes/class-wp-hook.php(288): call_user_func_array(Array, Ar in /var/www/u0674501/data/www/blog.psyalter.ru/wp-content/plugins/wp-testing/vendor/flourish/flourish/fGrammar.php on line 604