add prefer-encrypt metadata to autocrypt header
Actual Behavior:
Evolution does not add the prefer_encrypt metadata to the autocrypt header, it causes some email clients to answer unencrypted.
Expected Behavior:
Evolution systematically adds prefer-encrypt=mutual
to all autocrypt headers
Autocrypt: addr=alice@testrun.org; prefer-encrypt=mutual;
keydata=xjMEXt3z1xYJKwYBBAHaRw8BAQdAf6MctU/8cmEqwEN9VFZ3gHBFIxKiEaARZl1DFUkI7e
rNFTxob2N1cmkxQHRlc3RydW4ub3JnPsKLBBAWCAAzAhkBBQJe3fPXAhsDBAsJCAcGFQgJCgsCAxYC
ARYhBIZ3ajRUkki89+04sgctAtaIXygAAAoJEActAtaIXygAG2IA/1nTmmmkHAc1Bjtx2FOstbaS+N
XHjxaK+hkoWllsyhz0AQDJJ1++u7jVZPRn/j1LlByrT3Jv/D1aY14J5rjj+ADVBM44BF7d89cSCisG
AQQBl1UBBQEBB0DpSTaZ30dAVwM9PkBe2h+gFyxn9HSorP4XCHJu/lIdPAMBCAfCeAQYFggAIAUCXt
3z1wIbDBYhBIZ3ajRUkki89+04sgctAtaIXygAAAoJEActAtaIXygA2QkA/16toWCtseYKw8G1X2j7
xYR3Cyabq37hgbesDOThIIzNAP0UCUS8mnunmkS5adEbftRaDi2JZoGxDw46jtJJ2+13Cw==
Thanks!
Edited by Martin Monperrus