console.log 打印数组，有些为什么显示不完全

下面是 console.log 打印出来的
是22个
Array(22)， 只显示20个，length 也是 20

Array(22) [ "serial_number", "project_number", "client_number", "project_name", "Entrusted_unit", "construction", "supervising", "sender", "surveyor", "sender_phone", … ]
​
0: "serial_number"
​
1: "project_number"
​
2: "client_number"
​
3: "project_name"
​
4: "Entrusted_unit"
​
5: "construction"
​
6: "supervising"
​
7: "sender"
​
8: "surveyor"
​
9: "sender_phone"
​
10: "surveyor_phone"
​
11: "weld_name"
​
12: "weld_id"
​
13: "area"
​
14: "overview"
​
15: "Settlement_method"
​
16: "Settlement_state"
​
17: "remark"
​
18: "create_time"
​
19: "is_active"
​
length: 20

你是不是 又对 数组有啥操作了 。你看这个例子 把第三行去掉打印 就正常 。

let arr=["serial_number", "project_number", "client_number", "project_name", "Entrusted_unit", "construction", "supervising", "sender", "surveyor", "sender_phone"
    ,"serial_number", "project_number", "client_number", "project_name", "Entrusted_unit", "construction", "supervising", "sender", "surveyor", "sender_phone",
    "supervising", "sender"
    ];
    console.log(arr);
    arr=arr.splice(0,2);

什么问题，删除数组删不全？