Menus, messages and the errors Telex writes follow this language. Mail you write keeps its own words: each identity has its signature and its reply and forward headers (Accounts › Identities).
Identities
Who your mail is from. Each identity has its own signature and reply and forward headers. A reply is from the identity the message was sent to.
Sent mail waits this long in the Outbox. Z takes it back to change it.
Signatures and the reply and forward headers belong to each identity: Accounts › Identities.
A check downloads one small file from GitHub that names the newest version. It sends nothing about you, your mail or this copy of Telex. An update installs only when you choose, and only if it carries Telex’s signature.
This build of Telex can’t update itself. Release builds from telexmail.app can.