@gmiazga I am using Opera on Ubuntu 22.04. Both the latest opera-stable and opera-beta still seem to put keys in /etc/apt/trusted.gpg. I'm seeing this with:
opera-stable_84.0.4316.31_amd64.deb
opera-beta_85.0.4341.13_amd64.deb
I downloaded both just now.
$ sudo apt update
...
Get:10 https://deb.opera.com/opera-beta stable/non-free amd64 Packages [1,120 B]
...
All packages are up to date.
W: https://deb.opera.com/opera-beta/dists/stable/InRelease: Key is stored in legacy trusted.gpg keyring (/etc/apt/trusted.gpg), see the DEPRECATION section in apt-key(8) for details.
If I remove /etc/apt/trusted.gpg, it is restored when opera is purged and then reinstalled.
$ apt-key list
Warning: apt-key is deprecated. Manage keyring files in trusted.gpg.d instead (see apt-key(8)).
/etc/apt/trusted.gpg
--------------------
pub rsa4096 2019-09-12 [SC] [expired: 2021-09-11]
68E9 B2B0 3661 EE3C 44F7 0750 4B8E C3BA ABDC 4346
uid [ expired] Opera Software Archive Automatic Signing Key 2019 <packager@opera.com>
pub rsa4096 2021-06-23 [SC] [expires: 2023-06-23]
9FBD E02F 55F2 54D7 0082 1CCC DD3C 368A 8DE1 B7A0
uid [ unknown] Opera Software Archive Automatic Signing Key 2021 <packager@opera.com>
sub rsa4096 2021-06-23 [E] [expires: 2023-06-23]