use strict;
use warnings;
use WWW::Mechanize::Firefox;

my $mech = WWW::Mechanize::Firefox->new(
    activate => 1, # bring the tab to the foreground
);
$mech->get('https://familysearch.org/search/collection/results#count=20&query=%2Bevent_place_level_1%3ACalifornia%20%2Bevent_place_level_2%3A%22San%20Diego%22%20%2Bbirth_year%3A1923-1923~%20%2Bgender%3AM%20%2Brace%3AWhite&collection_id=2000219',':content_file' => 'main.html', synchronize => 0);

my $retries = 10;
    while ($retries-- and $mech->is_visible( xpath => '//*[@id="hourglass"]' )) {
     print "Sleep until we find the thing\n";
      sleep 2;
    };
     die "Timeout while waiting for application" if 0 > $retries;
   
    # Now the hourglass is not visible anymore

#fill out the search form
my @forms = $mech->forms();
#<input id="census_bp" name="birth_place" type="text" tabindex="0"/>    
#A selector prefixed with '#' must match the id attribute of the input. A selector prefixed with '.' matches the class attribute. A selector prefixed with '^' or with no prefix matches the name attribute.
$mech->field( birth_place => 'value_for_birth_place' );
# Click on the submit
$mech->click({xpath => '//*[@class="form-submit"]'});