Can't create a multichoice type of cloze question. When saving the question, moodle returns "Error reading from database". With debugging on, it prints:

Debug info: ERROR: invalid input syntax for integer: "B"
SELECT * FROM mdl_files WHERE contextid = $1 AND component = $2 AND filearea = $3 AND itemid = $4 ORDER BY id
[array (
0 => '13',
1 => 'user',
2 => 'draft',
3 => 'B',
)]
Stack trace:

line 393 of /lib/dml/moodle_database.php: dml_read_exception thrown
line 232 of /lib/dml/pgsql_native_moodle_database.php: call to moodle_database->query_end()
line 678 of /lib/dml/pgsql_native_moodle_database.php: call to pgsql_native_moodle_database->query_end()
line 1111 of /lib/dml/moodle_database.php: call to pgsql_native_moodle_database->get_records_sql()
line 1060 of /lib/dml/moodle_database.php: call to moodle_database->get_records_select()
line 266 of /lib/filestorage/file_storage.php: call to moodle_database->get_records()
line 627 of /lib/filelib.php: call to file_storage->get_area_files()
line 1058 of /question/type/questiontypebase.php: call to file_save_draft_area_files()
line 85 of /question/type/multichoice/questiontype.php: call to question_type->import_or_save_files()
line 424 of /question/type/questiontypebase.php: call to qtype_multichoice->save_question_options()
line 139 of /question/type/multianswer/questiontype.php: call to question_type->save_question()
line 424 of /question/type/questiontypebase.php: call to qtype_multianswer->save_question_options()
line 181 of /question/type/multianswer/questiontype.php: call to question_type->save_question()
line 264 of /question/question.php: call to qtype_multianswer->save_question()