TLS 1.3 support on iOS

Hi, I have a security-related feature request. As far as I can tell DC on iOS does not support TLS 1.3
I’m running my IMAP server on TLS 1.3 only. Android and flatpak clients can log in but on iOS the TLS handshake fails with the following error:

dovecot: imap-login: Disconnected: Connection closed: SSL_accept() failed: error:0A000102:SSL routines::unsupported protocol (no auth attempts in 0 secs):

Delta Chat: Error: error code -9806

I’m running Delta Chat v.1.32.0 on iOS 16.

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