Extending heading block results in fatal error

[glumanda]

I just tried to extend the heading block as mentioned in Blocks | Kirby CMS

So I’ve added

fields:
  blocks:
    type: blocks
    fieldsets:
      heading:
        extends: blocks/heading
        fields:
          customId:
            label: Custom ID
            type: text

to the /site/blueprints/blocks/heading.yml file, in order to extend it. When I open the panel and edit a page where I use the block editor, I always end up with following error:

[pixelijn]

@glumanda

to the /site/blueprints/blocks/heading.yml file,

The code you used only works in a page/file blueprint, where you define the blocks field. Otherwise, you have to make a copy of the heading.yml and make your changes as desired.

[glumanda]

Thank you @pixelijn!