If you use the TYPO3 (backend) scheduler task "ke_search:clearindex" and if database table "tx_kesearch_index" is filled. Then the error "Undefined constant 'STDIN'" occurs.
Only the execution via console is working because "STDIN" is only set in cli-mode.
The line 76 at ClearIndexCommand.php seems to be the problem:
$io->confirm($question, true)
If you use the TYPO3 (backend) scheduler task "ke_search:clearindex" and if database table "tx_kesearch_index" is filled. Then the error "Undefined constant 'STDIN'" occurs. Only the execution via console is working because "STDIN" is only set in cli-mode.
The line 76 at ClearIndexCommand.php seems to be the problem: $io->confirm($question, true)
Core: Exception handler (WEB): Uncaught TYPO3 Exception: Undefined constant 'STDIN' | Error thrown in file ...\typo3_src-10.4.14\vendor\symfony\console\Helper\QuestionHelper.php in line 110. Requested URL: http://domain.tld/typo3/index.php?route=%%2Fmodule%%2Fsystem%%2FtxschedulerM1&token=--AnonymizedToken--&CMD=toggleHidden&tx_scheduler[uid]=9