### ClickHouse release v20.8.12.2-lts FIXME as compared to v20.8.11.17-lts

#### Bug Fix
* Backported in [#18514](https://github.com/ClickHouse/ClickHouse/issues/18514): Restrict merges from wide to compact parts. In case of vertical merge it led to broken result part. [#18381](https://github.com/ClickHouse/ClickHouse/pull/18381) ([Anton Popov](https://github.com/CurtizJ)).