Keep getting errors from Table of Contents in some articles

[Lorenzo]

Hello, I randomly (it seems) get warning errors caused by the table of contents. When I get this error I usually delete the block and then create it again and the error disappear. Then, after days/weeks or months it reappear randomly.

What’s causing it?

Warning: array_filter() expects parameter 1 to be array, null given in /home/customer/www/grafigata.com/public_html/wp-content/plugins/ultimate-blocks/src/blocks/table-of-contents/block.php on line 10

Warning: array_values() expects parameter 1 to be array, null given in /home/customer/www/grafigata.com/public_html/wp-content/plugins/ultimate-blocks/src/blocks/table-of-contents/block.php on line 10

Warning: Invalid argument supplied for foreach() in /home/customer/www/grafigata.com/public_html/wp-content/plugins/ultimate-blocks/src/blocks/table-of-contents/block.php on line 18

In this article: https://www.grafigata.com/tecnologia/migliori-tavolette-grafiche/

• This discussion was modified 3 weeks, 1 day ago by  Lorenzo.

[Lorenzo]

And also here:

https://www.grafigata.com/tecnologia/i-migliori-portatili-per-fare-grafica/

https://www.grafigata.com/tecnologia/mouse-per-graphic-designer/

[Lorenzo]

I get this when I edit the article.

If I remove the block the error (of course) disappear.

And when I upload again the block the error doesn’t show up again:

https://www.grafigata.com/tecnologia/mouse-per-graphic-designer/

[Alexis]

Hi @Lorenzo ! Depending on when exactly the errors first came up, the Table of Contents in the previously-installed version of the plugin could have been incompatible with the one in the version you currently have. So far, we weren’t able to encounter the PHP errors in the frontend, and unless we see the error message on the console, we’d be unable to work towards recreating it on our end.

[Lorenzo]

So the error didn’t show up?

Now I fixed by removing and put it again the block but it’s very strange