job_bm_metabox_company_content_$id

add_filter('job_bm_metabox_company_navs','job_bm_metabox_company_navs_19082019', 90,2);

function job_bm_metabox_company_navs_19082019( $job_bm_settings_tab){

    $job_bm_settings_tab[] = array(
        'id' => 'custom_tab',
        'title' => sprintf(__('%s Custom','job-board-manager-company-profile'),'<i class="far fa-building"></i>'),
        'priority' => 1,
        'active' => true,
    );

    return $job_bm_settings_tab;

}

add_filter('job_bm_metabox_company_content_custom_tab','job_bm_metabox_company_content_custom_tab');

function job_bm_metabox_company_content_custom_tab( $post_id){


    ?>
    <div class="section">
        <div class="section-title"><?php echo __('Custom','job-board-manager-company-profile'); ?></div>
        <p class="section-description">Custom tab content</p>
    </div>

    <?php

}