I watched a TV show with Japanese subtitles, and noticed the sentence:
"秘密にしててほんとごめん。"
I was a bit confused because didn't know why there was a second て after the te-form of する. Because I didn't know how to look this up in my textbook or on Google, I asked a certain AI chatbot about it.
It tells me that してて is actually a contraction of していて (te-form of する and いる).
秘密にしててほんとごめん。 meaning "I'm really sorry for keeping it a secret."
秘密にしてほんとごめん。(without the second て) would only mean "I'm really sorry for making it a secret."
Is this correct?
Were you using simplelogin.io, which is part of Proton? It is actually possible to reply or send mails from the aliases you create there. The feature is called reverse-alias.