Different `utcOffset()` result in firefox and chrome

Describe the bug moment(new Date(1899, 11, 30, 0, 0, 0)).utcOffset()'s result is different in chrome and firefox

To Reproduce Steps to reproduce the behavior:

1. Open browser console and run above js.

Expected behavior The result should be correct and same in all environment

Desktop (please complete the following information):

• OS: windows 10
• Browser: firefox, chrome
• Version: latest realse

Moment-specific environment for js:

d = new Date(1899, 11, 30, 0, 0, 0);
[moment(d).utcOffset(),d.toString(),d.toLocaleString(),d.getTimezoneOffset(),Intl.DateTimeFormat().resolvedOptions()];
[new Date().toString(),new Date().toLocaleString(),new Date().toISOString()];

result in chrome:

[
  485,
  "Sat Dec 30 1899 00:00:00 GMT+0805 (中国标准时间)",
  "1899/12/30 上午12:00:00",
  -485,
  {
    "locale": "zh-CN",
    "calendar": "gregory",
    "numberingSystem": "latn",
    "timeZone": "Asia/Shanghai",
    "year": "numeric",
    "month": "numeric",
    "day": "numeric"
  }
]
["Wed May 06 2020 17:44:46 GMT+0800 (中国标准时间)", "2020/5/6 下午5:44:46", "2020-05-06T09:44:46.709Z"]

result in firefox:

[
  486,
  "Sat Dec 30 1899 00:00:00 GMT+0805 (中国标准时间)",
  "1899/12/30 上午12:00:00",
  -485.71666666666664,
  {
    "locale": "zh-Hans-CN",
    "calendar": "gregory",
    "numberingSystem": "latn",
    "timeZone": "Asia/Shanghai",
    "year": "numeric",
    "month": "numeric",
    "day": "numeric"
  }
]
[ "Wed May 06 2020 17:44:03 GMT+0800 (中国标准时间)", "2020/5/6 下午5:44:03", "2020-05-06T09:44:03.036Z" ]

Additional context The original issue is here: https://github.com/SheetJS/sheetjs/issues/1918 But I think you are professionals of datetime, and momentjs actually has the same issue, so I post issue here.