Manually adding the Opera RPM repository

Installing signing key

sudo rpm --import https://rpm.opera.com/rpmrepo.key

Fedora Instructions

sudo tee /etc/yum.repos.d/opera.repo <<RPMREPO
[opera]
name=Opera packages
type=rpm-md
baseurl=https://rpm.opera.com/rpm
gpgcheck=1
gpgkey=https://rpm.opera.com/rpmrepo.key
enabled=1
RPMREPO

sudo dnf install opera-developer

OpenSUSE Instructions

sudo tee /etc/zypp/repos.d/opera.repo <<RPMREPO
[opera]
name=Opera packages
type=rpm-md
baseurl=https://rpm.opera.com/rpm
gpgcheck=1
gpgkey=https://rpm.opera.com/rpmrepo.key
enabled=1
autorefresh=1
keeppackages=0
RPMREPO

sudo zypper in opera-developer

The GPG fingerprint

For your reference, the fingerprint of the current GPG key is:

2023 key

pub   rsa4096 2023-05-29 [SC] [expires: 2025-05-28]
      9701D4A1B4D92E261C8C66FE24A1004B1F11DCC9
      uid           [ultimate] Opera Software Archive Automatic Signing Key 2023 
      sub   rsa4096 2023-05-29 [E] [expires: 2025-05-28]