For about 4 months, I can't add ppa's. I upgraded to deepin 15.4.1 and I still can't. When I try, this is the output:~$ sudo add-apt-repository ppa:santilli-gabriele/slic3r-prusa
[sudo] password for alex:
Allows installing the Prusa Edition of Slic3r.
More info: https://launchpad.net/~santilli-gabriele/+archive/ubuntu/slic3r-prusa
Press [ENTER] to continue or ctrl-c to cancel adding it

gpg: keybox '/tmp/tmpmot5y8t8/pubring.gpg' created
gpg: failed to start the dirmngr '/usr/bin/dirmngr': No such file or directory
gpg: connecting dirmngr at '/tmp/tmpmot5y8t8/S.dirmngr' failed: No such file or directory
gpg: keyserver receive failed: No dirmngr

~$ sudo add-apt-repository ppa:santilli-gabriele/slic3r-prusa