@vipin I applied the patch but (don't know if is the patch that cause the issue) as customer I receive the custom email link in English and not Italian that is my default language.

Customer click on the ticket number or receive the registration email and this have the link point to en language. Why if Italian should be the default for me?

OK tested and seems is not your patch but the issue returned to be after one of your updates.

Update: Resolved (see the GitHub issue)