WP 5.0. breaks page builder. See fix here

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Sometimes, when installing the theme from WordPress dashboard, the following error occurs:

This is one of the most unhelpful error because it doesn't say anything and there can be a lot of factors that lead to this. However, in most of the cases, this error is fixed by uploading the theme using FTP instead of WordPress dashboard.

Here's a full tutorial on how to install the theme via FTP: https://socanny.ticksy.com/article/11332