### ClickHouse release v21.8.10.19-lts FIXME as compared to v21.8.9.13-lts

#### Improvement
* Backported in [#30452](https://github.com/ClickHouse/ClickHouse/issues/30452): Allow symlinks to files in user_files directory for file table function. [#30309](https://github.com/ClickHouse/ClickHouse/pull/30309) ([Kseniia Sumarokova](https://github.com/kssenii)).

#### Bug Fix (user-visible misbehaviour in official stable or prestable release)

* Backported in [#29724](https://github.com/ClickHouse/ClickHouse/issues/29724): Fix null deference for `GROUP BY WITH TOTALS HAVING` (when the column from `HAVING` wasn't selected). [#29553](https://github.com/ClickHouse/ClickHouse/pull/29553) ([Azat Khuzhin](https://github.com/azat)).
* Backported in [#30233](https://github.com/ClickHouse/ClickHouse/issues/30233): Fix INSERT SELECT incorrectly fills MATERIALIZED column based of Nullable column. [#30189](https://github.com/ClickHouse/ClickHouse/pull/30189) ([Azat Khuzhin](https://github.com/azat)).
* Backported in [#30333](https://github.com/ClickHouse/ClickHouse/issues/30333): * Allow identifiers staring with numbers in multiple joins. [#30230](https://github.com/ClickHouse/ClickHouse/pull/30230) ([Vladimir C](https://github.com/vdimir)).
* Backported in [#30377](https://github.com/ClickHouse/ClickHouse/issues/30377): fix replaceRegexpAll bug. [#30292](https://github.com/ClickHouse/ClickHouse/pull/30292) ([Memo](https://github.com/Joeywzr)).