Creates a dropdown with all event categories Has to be added to template where the dropdown should be displayed. Sources: https://theeventscalendar.com/support/forums/topic/category-dropdown/ https://pastebin.com/jg2hr5yz

dropdown.php

 <?php 
            $categories = get_categories(
                array(
                   'taxonomy'      => TribeEvents::TAXONOMY,
                   'selected'      => 0,
                   'orderby'       => 'name'
                ) );
            ?>

            <script type="text/javascript"><!--
            function onCatChange(select) {
                var slug = select.options[select.selectedIndex].value;
                var link = '<?= tribe_get_events_link() ?>';
                location.href = (slug == 'all') ? link : link + 'category/' + slug;
            }
            --></script>

            <select id="categories" onchange="onCatChange(this)" >
                <option value="all">All Events</option>
                <?php
                foreach ($categories as $cat) {
                    if (tribe_meta_event_category_name() == $cat->name) $selected='selected';
                    else $selected = '';
                ?>
                <option value="<?= $cat->slug ?>" <?= $selected ?>><?= $cat->name ?></option>
                <?php } ?>
            </select>