fatal error: Argument 1 passed to MessageHandle::__construct() must be an instance of Title, null given in /srv/mediawiki/php-1.28.0-wmf.14/extensions/Translate/utils/MessageHandle.php on line 37
This is super frustrating. The error message does not specify anything about the caller and there is no backtrace in logstash. In other words the only thing I can do is to remove the typehint, patch in a manual check and throw an exception with a backtrace.
That's the wrong version numbers. It's wmf.13 and wmf.14. https://gerrit.wikimedia.org/r/#/c/303372/4/TranslateHooks.php got introduced in wmf.14 so I guess it's related to that although the doc says it will be a Title object.
Debug log says:
Got non-Title in AbuseFilterHooks::onUploadStashFile/AbuseFilterHooks::filterUpload/AbuseFilter::filterAction/Hooks::run/TranslateHooks::onAbuseFilterFilterAction
Can file a new task for fixing that.