But nothing works. In fact, after clicking to select a key (‘My Key’ option), a window appears with the title OpenKeychain asking me to encrypt end-to-end for my email address. But no key is shown in this window; only “create a new encryption key”, or “import a key” from another device, or “desactivate”. But the key imported into OpenKeychain that I need doesn’t appear and I can’t actually use it with K9-Mail.