json extractors not work with non-english field name

I have send some json message via raw udp input, each json message contain UTF-8 non-english field name like this:
When I try json extractor with default config,seems work good as below:
So I add json extractor like this and also try passed.
Configuration

flatten:
list_separator: ,
kv_separator: =
key_prefix: j_
key_separator: _
replace_key_whitespace:
key_whitespace_replacement: _

## Expected Behavior

I can see some english field works with json extractor:

But non-english field can not see:

Here is my json message example:
{"source":"stream:icmp","sourcetype":"icmp","time":1632071413.6059999466,"endtime":"2021-09-19T17:10:13.606360Z","timestamp":"2021-09-19T17:10:13.606360Z","字节":135,"入向字节":135,"出向字节":0,"校验和":33039,"消息代码":0,"目标ip":"100.100.10.6","目标mac":"D2:AE:52:6C:52:47","标识符":2570,"详细协议":"ip:icmp","序列号":2631,"源ip":"100.10.10.12","源mac":"01:50:56:9A:F3:D9","总用时":0,"消息类型":5,"类型说明":"Redirect"}

Thank you for your help

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