retry($ua, $url, $fr1);
...
sub retry { # Retry downloading page in case of failure
    my $ua=shift;
    my $url=shift;
    for (my $i=1; $i<101; $i++) {
        sleep 5; # Delay
        my $request= $ua->request(GET "$url");
        return $request if ($request->is_success);
        $fr1->Label(-text=>'Download failed: ' . $request->status_line, -background=>'yellow', -foreground=>'red')->pack(-fill=>'y'); 

.....