grep 'Завершившийся процесс выполнял действие' src/backend/po/ru.po -B 1
msgid "Failed process was running: %s"
msgstr "Завершившийся процесс выполнял действие: %s"

git grep 'Failed process was running'

activity = pgstat_get_crashed_backend_activity(...

This function is only intended to be used by the postmaster to report the
 *	query that crashed a backend.