您可以使用match而不是split，然后在多行文字以\r\n?分隔时进行比对。
下面是一个代码片段，其中包含原始方法和建议的方法：

const message = 'Hello, please can you send £100.00 to  MNBVCXZLSTERIA1 on  04/08/21  \n\nhttps://www.co-operativebank.co.uk/help-and-support/faqs/accounts/savings/isas/ \r\nwhat-happens-if-i-put-too-much-money-in-my-cash-isa/PROD-2740 \n\nThank you';
// With look-behind
const messageArray = message.split(/(?<!\r)\n/gm);
console.log(messageArray);
// Without lookbehind
const messageArray2 = message.match(/^.*$(\r\n?.*$)*/gm);
console.log(messageArray2);

输出相同。

假设\r\n仅位于链接内，而\n位于链接外，您可以先通过删除\r\n来恢复链接，然后按\n进行拆分：

const input = 'Hello, please can you send £100.00 to  MNBVCXZLSTERIA1 on  04/08/21  \n\nhttps://www.co-operativebank.co.uk/help-and-support/faqs/accounts/savings/isas/ \r\nwhat-happens-if-i-put-too-much-money-in-my-cash-isa/PROD-2740 \n\nThank you';
let result = input.replace(/ *\r\n/g, '').split(/\n/);
console.log(result);

输出量：

[
  "Hello, please can you send £100.00 to  MNBVCXZLSTERIA1 on  04/08/21  ",
  "",
  "https://www.co-operativebank.co.uk/help-and-support/faqs/accounts/savings/isas/what-happens-if-i-put-too-much-money-in-my-cash-isa/PROD-2740 ",
  "",
  "Thank you"
]

注意：要删除空数组项，您可以改为使用以下命令：.split(/\n+/)