It just occured to me that cmd.exe is windows-only

Common/PasswordGenerator.cs

@@ -35,6 +35,14 @@ public static class PasswordGenerator
     {
         ProcessBuilder pb = new ProcessBuilder();
         pb.ProcessFailed += (e) => ExceptionOccured?.Invoke(e);
-		return pb.GetOutput("cmd.exe", $"echo {RandomStr(length, no_symbols)} | gpg --quiet --encrypt --recipient {recipient}");
+
+		if (System.Runtime.InteropServices.RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+		{
+			return pb.GetOutput("cmd.exe", $"echo {RandomStr(length, no_symbols)} | gpg --quiet --encrypt --recipient {recipient}");
+		}
+		else
+		{
+			return pb.GetOutput("echo", $"{RandomStr(length, no_symbols)} | gpg --quiet --encrypt --recipient {recipient}");
+		}
     }
 }