Evert

Thank you. Almost there!

On variable products the Add to cart section is visible again, but there is still an error: https://www.dropbox.com/s/3ocp4y7vltez2cq/Screenshot%202016-01-04%2017.12.45.png?dl=0

Thanks Mike!

Best is to revert to the default theme without plugins enabled and enable all plugins one by one for troubleshooting.

@cayonone I have just tried the suggested code and I can confirm it is working (beside a missing end tag of the unordered list ) on my dev server.

Try replacing the content of your-theme/job_manager/job-filter-job-types.php with the following:

<?php if ( ! is_tax( 'job_listing_type' ) && empty( $job_types ) ) : ?>
    <ul class="job_types">
        <?php foreach ( get_job_listing_types() as $type ) : ?>
            <li><label for="job_type_<?php echo $type->slug; ?>" class="<?php echo sanitize_title( $type->name ); ?>"><input type="checkbox" name="filter_job_type[]" value="<?php echo $type->slug; ?>" id="job_type_<?php echo $type->slug; ?>" /> <?php echo $type->name; ?></label></li>
        <?php endforeach; ?>
    </ul>
<?php elseif ( $job_types ) : ?>
    <?php foreach ( $job_types as $job_type ) : ?>
        <input type="hidden" name="filter_job_type[]" value="<?php echo sanitize_title( $job_type ); ?>" />
    <?php endforeach; ?>
<?php endif; ?>

I’ve just spotted a javascript error on your site (st_go not defined) which looks related to WordPress.com stats.

What template + other plugins are you using? As far as I know there are no share buttons added by the plugin.

If I am correct you can change the %s values by defining the language of your WordPress installation. You can do so in your wp-config.php.

For example
define( 'WPLANG', 'de_DE' );

See http://codex.ww.wp.xz.cn/Installing_WordPress_in_Your_Language for the instructions. Note that you will have to use the appropriate country_languages codes. There are two links on the above page that can help you find the right combination.