Changing phone number on messaging apps.
#Signal: Confirm your new phone number, done.
#Telegram: Confirm your new phone number, done.
#WhatsApp: Confirm your new phone number. Have 50 new notifications "You were added to this group" for all the groups that I'm part of since the last many years. At least it kept the chat history, I'd have expected it to lose that also, based on other contacts that have changed their number at some point.