If you are having issues in the backend, such as the Theme Settings metabox not rendering correctly or the WPBakery page builder not loading, it’s possible that the SubstituteMaxLineLength setting in your server configuration needs adjustment. While this issue can happen on any hosting provider, we’ve most often seen it occur on GoDaddy.
You can try adding the following code to your .htaccess file:
<IfModule mod_substitute.c>
SubstituteMaxLineLength 10M
</IfModule>If you’re not comfortable editing .htaccess yourself, or if this doesn’t resolve the issue, you can also contact your web host and ask them to update the SubstituteMaxLineLength for you.
If you still have issues after that, please let us know!