This can be used to verify the authenticity of Electrum binaries/sources.
Download only from electrum.org and remember to check the gpg signature again every time you download a new version
In a terminal enter (or copy):
gpg --keyserver keys.gnupg.net --recv-keys 6694D8DE7BE8EE5631BED9502BD5824B7F9470E6
You should be able to substitute any public GPG keyserver if keys.gnupg.net is (temporarily) not working
Download the Python Electrum-<version>.tar.gz or AppImage file
Right click on the signature file and save it as well
Run the following command from the same directory you saved the files replacing <electrum file> with the one actually downloaded:
gpg --verify <electrum file>.asc <electrum file>
The message should say:
Good signature from "Thomas Voegtlin (https://electrum.org) <thomasv@electrum.org>
and
Primary key fingerprint: 6694 D8DE 7BE8 EE56 31BE D950 2BD5 824B 7F94 70E6
You can ignore this:
WARNING: This key is not certified with a trusted signature!
gpg: There is no indication that the signature belongs to the owner.
as it simply means you have not established a web of trust with other GPG users