Error
Request URL: /rpc/runSingleJob.php
Request ID: not applicable
From the logs:
2019-04-18 10:58:41 [799c42dbfaeda1474c477c48] mw1306 metawiki 1.34.0-wmf.1 JobExecutor ERROR: Failed creating job from description {"job_type":"MassMessageJob","message":"Title Special: is invalid"}
Impact
A lot of jobs (most notably, cdnPurge and MassMessage that I found) are failing to execute. See for example T221365 as impact