The last two runs of mediawiki_job_generatecaptcha have failed in production with the following error:
Mar 4 09:41:00 mwmaint2002 mediawiki_job_generatecaptcha[41908]: Copying the new captchas to storage...Fatal error: require(): Failed opening required '/srv/mediawiki/php-1.42.0-wmf.20/includes/json/FormatJson.php' (include_path='/srv/mediawiki/php-1.42.0-wmf.20/vendor/pear/console_getopt:/srv/mediawiki/php-1.42.0-wmf.20/vendor/pear/mail:/srv/mediawiki/php-1.42.0-wmf.20/vendor/pear/mail_mime:/srv/mediawiki/php-1.42.0-wmf.20/vendor/pear/net_smtp:/srv/mediawiki/php-1.42.0-wmf.20/vendor/pear/net_socket:/srv/mediawiki/php-1.42.0-wmf.20/vendor/pear/net_url2:/srv/mediawiki/php-1.42.0-wmf.20/vendor/pear/pear-core-minimal/src:/srv/mediawiki/php-1.42.0-wmf.20/vendor/pear/pear_exception:/srv/mediawiki/php-1.42.0-wmf.20:/usr/local/lib/php:/usr/share/php') in /srv/mediawiki/php-1.42.0-wmf.20/includes/AutoLoader.php on line 223
Feb 26th run was able to be re-started manually during the day, and finished without errors. The last one (Mar 4th) was restarted twice without being able to do a complete run. It actually failed earlier in the script loop on the second attempt.