After loading saved optimizer context, further queries cause errors

create database if not exists m8;use m8;

drop table t1;

create table t1(a int);

set optimizer_record_context=ON;

explain select * from t1;

SELECT context INTO DUMPFILE 'context1.txt' FROM INFORMATION_SCHEMA.OPTIMIZER_CONTEXT;

source data2/m8/context1.txt;

drop table if exists t2;

create table t2( a int);

insert into t2 select seq from seq_1_to_10;