Thanks forrest. But I am wondering, whether it is that easy, even with a PC “at hand”:
user@host:~/Downloads/android$ gpg --search-keys f-droid
gpg: data source: http://192.146.137.99:11371
(1) Launchpad PPA for F-Droid
4096 bit RSA key EC4632C79C5E0151, created: 2016-09-14
(2) Launchpad PPA for F-Droid
4096 bit RSA key 217AF6E2A2BC641F, created: 2016-09-14
(3) F-Droid admin@f-droid.org
4096 bit RSA key 41E7044E1DBA2E89, created: 2014-04-25
Keys 1-3 of 3 for “f-droid”. Enter number(s), N)ext, or Q)uit > Q
gpg: error searching keyserver: Operation cancelled
gpg: keyserver search failed: Operation cancelled
user@host:~/Downloads/android$ gpg --verify FDroid.apk.asc
gpg: assuming signed data in ‘FDroid.apk’
gpg: Signature made Do 11 Apr 2019 14:41:19 CEST
gpg: using RSA key 7A029E54DD5DCE7A
gpg: Can’t check signature: No public key
So which one should be imported? This issue is also linked with PGP-signature of F-Droid.apk
Any thoughts are appreciated!