SyntaxError: Invalid regular expression: /^((((+|0{2})3876)|06)[0-6])((?<=4)\d{7}|(?<!4)\d{6})$/: Invalid group
Did not have this until yesterday (when I was on v13.0.0). When I was looking at npm, saw that a new version was upgraded just around 20 hours ago. Also the regular expression pointed out in the error was added in the new version:
Click here to view the changeset which includes the below regular expression

Error on starting service when the module is required:

/usr/app/node_modules/validator/lib/isMobilePhone.js:14
var phones = {
             ^
SyntaxError: Invalid regular expression: /^((((\+|0{2})3876)|06)[0-6])((?<=4)\d{7}|(?<!4)\d{6})$/: Invalid group
    at Object.<anonymous> (/usr/app/node_modules/validator/lib/isMobilePhone.js:14:14)
    at Module._compile (module.js:643:30)
    at Object.Module._extensions..js (module.js:654:10)
    at Module.load (module.js:556:32)
    at tryModuleLoad (module.js:499:12)
    at Function.Module._load (module.js:491:3)

Validator.js version: 13.1.0
Node.js version: v8.9.4
OS platform: macOS

Happened when running app in a docker container.