By default, widgets in WordPress don’t accept shortcodes. That means if you try adding a popup trigger into your sidebar or footer (which is a smart idea), you’ll notice the actual text of the shortcode appears instead of your popup trigger.
This goes for the MD Text + Image widget as well. Luckily, the fix is easy! Just paste this single line of code into your Child Theme’s
functions.php file and shortcodes will now properly output in your Text widgets.
add_filter( 'widget_text', 'do_shortcode' );
PRO TIP: Make sure your Child Theme is activated from the
Appearance > Themes menu.