$ gpg --version | sed -n '1,2p'
gpg (GnuPG) 2.4.8
libgcrypt 1.11.1-unknown

In ''/home/$USER/.gnupg/''

• file ''gpg.conf'' doesn't exist
• ''common.conf'' exists.
• No preferred key-server specified as default in any configuration file.

$ gpg -v --search-keys 55aa81128cffff46df140838bc187a13ad10060b
[...]
gpg: data source: https://185.125.188.27:443
gpg: key "..." not found on keyserver
gpg: keyserver search failed: Not found

Hello. The wording resulting from '-v' would benefit from being fully descriptive. Without knowing from the GPG(1) documentation or the details printed here what might lead to determine whether there might be an issue causing the key not to be found, at best can be done extrapolations.

• Is the search being done by multiple key-servers or jut one?
  • If done by just one, is the key-server arbitrarily chosen?
  • If done by multiple, is the printed IP address the one associated to the name of the last resort domain?

$ nslookup 185.125.188.27
27.188.125.185.in-addr.arpa	name = keyserver.ubuntu.com.

Authoritative answers can be found from:

Is specified here the user ID to which the key ID is associated.

$ gpg-wks-client -vv --supported opensource@proton.me
gpg-wks-client: reading options from '/home/[...]/.gnupg/common.conf'
gpg-wks-client: provider for 'opensource@proton.me' does NOT support WKS

However I cannot conclude that GnuPG internally sets a preferred domain by default, nor can I rule out this possibility. Could the domain ''keys.openpgp.org'' have been chosen, for example? Since it is impossible to know whether the user ID(s) associated with the specified key ID have been set as the preferred key server, allowing third-party users to know where to obtain the key, it is impossible to know whether the chosen domain name indicates an issue. So I am reporting it.