To repeat: ./mtr --mem  --charset-for-testdb=utf8mb4

Fix for
func_in_all
func_in_icp
func_in_icp_mrr
func_in_mrr
func_in_mrr_cost
func_in_none

opt_trace.filesort_pq
opt_trace.filesort_pack
main.filesort_pack

fulltext
fulltext_left_join