update compatibility changes

releases/release-8.1.0.md

@@ -177,19 +177,19 @@ Compared with the previous LTS 7.5.0, 8.1.0 includes new features, improvements,
 |--------|------------------------------|------|
 | [`tidb_auto_analyze_ratio`](/system-variables.md#tidb_auto_analyze_ratio) | Modified | Changes the value range from `[0, 18446744073709551615]` to `(0, 1]`. |
 | [`tidb_enable_dist_task`](/system-variables.md#tidb_enable_dist_task-new-in-v710) | Modified | Changes the default value from `OFF` to `ON`. This means that Distributed eXecution Framework (DXF) is enabled by default, which fully utilizes the resources of the TiDB cluster and greatly improves the performance of `ADD INDEX` and `IMPORT INTO` tasks. If you want to upgrade a cluster with the DXF enabled to v8.1.0 or later, disable the DXF (by setting `tidb_enable_dist_task` to `OFF`) before the upgrade, which avoids `ADD INDEX` operations during the upgrade causing data index inconsistency. After the upgrade, you can manually enable the DXF. |
-| [`tidb_service_scope`](/system-variables.md#tidb_service_scope-new-in-v740) | Modified  | Changes the optional value from  "" or `background` to a string with a length of up to 64 characters, which enables you to control the service scope of each TiDB node more flexibly. Valid characters include digits `0-9`, letters `a-zA-Z`, underscores `_`, and hyphens `-`. The Distributed eXecution Framework (DXF) determines which TiDB nodes can be scheduled to execute distributed tasks based on the value of this variable. For specific rules, see [Task scheduling](/tidb-distributed-execution-framework.md#task-scheduling). |
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+| [`tidb_service_scope`](/system-variables.md#tidb_service_scope-new-in-v740) | Modified | Changes the optional value from `""` or `background` to a string with a length of up to 64 characters, which enables you to control the service scope of each TiDB node more flexibly. Valid characters include digits `0-9`, letters `a-zA-Z`, underscores `_`, and hyphens `-`. The Distributed eXecution Framework (DXF) determines which TiDB nodes can be scheduled to execute distributed tasks based on the value of this variable. For specific rules, see [Task scheduling](/tidb-distributed-execution-framework.md#task-scheduling). |
 
 ### Configuration file parameters
 
 | Configuration file | Configuration parameter | Change type | Description |
 | -------- | -------- | -------- | -------- |
-| TiDB Lightning | [`conflict.threshold`](/tidb-lightning/tidb-lightning-configuration.md#tidb-lightning-task) | Modified | Changes the default value from `9223372036854775807` to `10000` to quickly interrupt abnormal tasks so that you can make corresponding adjustments as soon as possible. This saves time and computational resources by avoiding the scenario where a large amount of conflicting data is discovered after the import, caused by abnormal data sources or incorrect table schema definitions. |
 | TiDB Lightning | [`conflict.max-record-rows`](/tidb-lightning/tidb-lightning-configuration.md#tidb-lightning-configuration) | Modified | Starting from v8.1.0, there is no need to configure `conflict.max-record-rows` manually, because TiDB Lightning automatically assigns the value of `conflict.max-record-rows` with the value of `conflict.threshold`, regardless of the user input. `conflict.max-record-rows` will be deprecated in a future release. |
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+| TiDB Lightning | [`conflict.threshold`](/tidb-lightning/tidb-lightning-configuration.md#tidb-lightning-task) | Modified | Changes the default value from `9223372036854775807` to `10000` to quickly interrupt abnormal tasks so that you can make corresponding adjustments as soon as possible. This saves time and computational resources by avoiding the scenario where a large amount of conflicting data is discovered after the import, caused by abnormal data sources or incorrect table schema definitions. |
+| TiCDC | [`security.client-allowed-user`](/ticdc/ticdc-server-config.md#cdc-server-configuration-file-parameters) | Newly added | Lists the usernames that are allowed for client authentication. Authentication requests with usernames not in this list will be rejected. The default value is null. |
+| TiCDC | [`security.client-user-required`](/ticdc/ticdc-server-config.md#cdc-server-configuration-file-parameters) | Newly added | Controls whether to use username and password for client authentication. The default value is `false`. |
+| TiCDC | [`security.mtls`](/ticdc/ticdc-server-config.md#cdc-server-configuration-file-parameters) | Newly added | Controls whether to enable the TLS client authentication. The default value is `false`. |
+| TiCDC | [`sink.debezium.output-old-value`](/ticdc/ticdc-changefeed-config.md#changefeed-configuration-parameters) | Newly added | Controls whether to output the value before the row data changes. The default value is true. When it is disabled, the UPDATE event does not output the "before" field. |
+| TiCDC | [`sink.open.output-old-value`](/ticdc/ticdc-changefeed-config.md#changefeed-configuration-parameters) | Newly added | Controls whether to output the value before the row data changes. The default value is true. When it is disabled, the UPDATE event does not output the "p" field. |
 
 ### Others