It seems there is a script which is not compatible with Merge Scripts.

​You can try to enable/disable Async Execute first, if it won’t solve the issue, you may need to exclude the problematic script.

To find it, please following these steps:

  1. Enable logging on General tab and set the loglevel to Error
  2. Clear the cache for the homepage, and recache it.
  3. Open the page in incognito window, and check the error message in the console.
  4. Click to the error message, it will open the script and jumpt to the problematic line. Please find the comment above this line (eg: /*https://yoursite.com/wp-content/plugins/plugin-name/assets/plugin.js*/), and exclude the problematic file from merging (add script URL to Footer Scripts, eg: /wp-content/plugins/plugin-name/assets/plugin.js).

Please note, if the excluded javascript has some dependencies, may it will lead other javascript errors (eg: “jQuery is not defined”). If you get more errors, you may need to exclude all dependencies (eg: jQuery.js, all scripts for the plugin).