Replacing screen
Good afternoon, after replacing the screen in iphone 8, should the true tone function be active?
Well, a screen replacement can produce some changes in settings. It's a good practice to perform a complete check of settings after any hardware service.
Generally, if your iPhone has been serviced at an Apple Store or Authorized Service Provider, that shouldn't happen (they have specific tools to control all the internal components and settings), and most of all you're sure they are using a genuine Apple spare part. And, in any case, after their service, you can take your device back to them and ask for a free check / adjustment (if needed)
Regards
Giulio