WP-Members has always focused on content contained in the WordPress $content variable. More recently, the popularity of builder plugins such as Page Builder by SiteOrigin or Elegant Builder from Elegant Themes has raised the issue of blocking content that is not necessarily stored in the same manner.
Note: as of version 3.0.4, the priority of WP-Members filter hooked to the_content has been changed to accommodate builder plugins. The priority is now 99, so unless another plugin sets its priority at 100 or higher, WP-Members will come after it (which is what you want). I’ve left the information in this post intact as it may be useful for some applications, but for most users, it will be unnecessary.
The post focuses on the general approach to blocking content from these types of plugins and includes code snippets you can use for the two plugins mentioned above.