Comment 3 for bug 1312267

This bug was fixed in the package software-properties - 0.96.24.25

---------------
software-properties (0.96.24.25) bionic; urgency=medium

  * ppa.py:
   - rework key retrieval, instead of using hkp & gnupg/dirmngr, use https
     & python's built in urllib.
   - thus, add-apt-key for PPAs observes https_proxy for key retrieval
   - simplify gnupg operations, depend on gpg package only, and use
     import/public key operations only.
   - fix unicode process output bugs, when operating in a non-UTF-8
     locale, thus enabling to import keys for my ppas in C locale.
   - avoid creating trustdb, or requiring any gpg-agent systemd socket to
     be activated
   - update tests to execute key addition fully with less things stubbed
     out with mock
   - stop using apt-key for installing keys
   - dirmngr is a heavy dependency and not used, and it is hard to pass
     proxy information to it when invoking gpg from a non-standard homedir
   - deprecate --keyserver option, making HTTPS access to
     keyserver.ubuntu.com required
   - LP: #1755192, LP: #1713962, LP: #1699086, LP: #1510220, LP: #1433761,
     LP: #1395321, LP: #1312267

 -- Dimitri John Ledkov <email address hidden> Mon, 02 Apr 2018 10:19:34 +0100