TypeScript SDK causes errors when user browses in Incognito mode

Code examples:

import { init } from '@amplitude/analytics-browser'
init(process.env.AMPLITUDE_TOKEN, null, {
  serverZone: ServerZone.EU,
})

import {
  setOptOut,
  Identify,
  identify,
  setUserId,
} from '@amplitude/analytics-browser'

if (isUserInternal(ua)) {
// Opt-out internal users from Amplitude tracking
  setOptOut(true)
} else {
  const userIdentify = new Identify()
  setUserId(ua?.id)
  userIdentify.set('userName', ua?.name)
  userIdentify.set('userEmail', ua?.username)
  identify(userIdentify)
}

Expected Behavior

I'm aware that Amplitude & other analytics tools can be blocked in the browser's Incognito mode and by script blocking tools. However, I would expect Amplitude to not track the user in this case, not to throw errors and crash my application.

Current Behavior

In browser incognito mode, Amplitude is probably blocked. init method seems to work ok (doesn't throw any errors), but then when executing setOptOut or setUserId methods, user gets the following errors:

TypeError: Cannot set properties of undefined (setting 'optOut')
at AmplitudeBrowser.setOptOut

TypeError: Cannot set properties of undefined (setting 'userId')
at AmplitudeBrowser.setUserId

Possible Solution

This problem doesn't exist in JavaScript SDK. I needed to switch back to using JavaScript SDK (which is marked as legacy now) to solve this problem.

I suppose this problem could be caused by a lack of instance object in TypeScript SDK. There is no amplitude object to check if it exists and no getInstance method. Maybe merging this pull request could be helpful: https://github.com/amplitude/Amplitude-TypeScript/pull/106

Maybe a method to check if Amplitude is initialized could solve this problem: https://github.com/amplitude/Amplitude-TypeScript/issues/169

Steps to Reproduce

Initialize Amplitude TypeScript SDK
Use setOptOut or setUserId methods
Run application in browser incognito mode

Environment

TypeScript SDK Version: "@amplitude/analytics-browser": "^1.0.3"
Installation Method: Yarn
Browser and Version: Chrome Version 103.0.5060.134 (Incognito mode)

amplitude / Amplitude-TypeScript