Hello,
First of all, you are using the Child Theme on your site, and also the old version of the Parent-Theme, you have to activate the Parent-Theme first and then update the Parent-Theme to the very latest version (25-08-2020 – Update version 5.2.0).
1. Make a full backup of your website files and database.
2. Turn off all optimizations and cache plugins. Temporarily disable CDN if applied.
3. Switch to parent theme if you are running a child theme.
4. Update the theme in one of the traditional ways described in our documentation https://xtemos.com/docs/woodmart/update-theme-2/
5. Clear your browser cache.
6. Test if everything is working correctly.
7. Regenerate CSS generator if applied and resave Theme Settings.
Now before Turn ON the disabled plugins and Child Theme and the cache like CDN, try to clear the browser cache and check back the functionality of the Mega Menu (HTML Block) dropdown, If the issue solved then you can Turn on disabled plugins and a child theme. Clear their cache and CDN.
And if the issue will still persist then remain all the third-party plugins deactivated and share the site WP-Admin Login details in the private content area of this topic so that I’ll debug it for you.
The Detail of the Feature how it works: A mega menu expands the default WordPress drop-down menu allowing to show a sales product, images, nice menu items. Megamenu block can be set in Appearance – > Menu -> Select Menu -> Enter menu item – > Set the HTML block from the dropdown list: https://xtemos.com/wp-content/uploads/screenshots/woodmart/megamenu.png
Regard’s.
Xtemos Studio.
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