Hello!

There are many reports here https://www.zabbix.com/forum/in-russian/376848-%D0%BF%D1%80%D0%BE%D0%B1%D0%BB%D0%B5%D0%BC%D0%B0-%D0%BF%D1%80%D0%B8-%D0%B0%D0%BF%D0%B3%D1%80%D0%B5%D0%B9%D0%B4%D0%B5-%D1%81-4-0-6-%D0%B4%D0%BE-4-2

about failed database upgrade

[Z3005] query failed: [1071] Specified key was too long; max key length is 767 bytes [create unique index lld_macro_path_1 on lld_macro_path (itemid,lld_macro)]

There are nothing in upgrade notes about this.