Fatal error during a configuration of a TOC block in a Layout Builder

Problem/Motivation

The module throws a fatal error during an attempt to add a TOC block to a Layout Builder section.

Steps to reproduce

1. Install the TOC API module, TOC Filter and Layout Builder modules.
2. Go to a Text Filter and activate a checkbox to show a TOC in a block
3. Activate a Layout Builder mode for a content type display.
4. Try to add a TOC block to a Layout Builder section.
5. See the fatal error.

Proposed resolution

Add a check if the $toc object is empty during a block rendering.