$snap install ubuntu-core >> error: cannot install "ubuntu-core": Get https://search.apps.ubuntu.com/api/v1/snaps/details/ubuntu-core?confinement=strict: x509: certificate signed by unknown authority
snap 2.13+ppa207-1 snapd 2.13+ppa207-1 series 16 ubuntu 16.04
System use proxy.
$snap install ubuntu-core /search. apps.ubuntu. com/api/ v1/snaps/ details/ ubuntu- core?confinemen t=strict: x509: certificate signed by unknown authority
>> error: cannot install "ubuntu-core": Get https:/
snap 2.13+ppa207-1
snapd 2.13+ppa207-1
series 16
ubuntu 16.04
System use proxy.