This is the default blueprint for the heading block type:
name: field.blocks.heading.name
icon: title
wysiwyg: true
preview: heading
fields:
level:
label: field.blocks.heading.level
type: select
empty: false
default: "h2"
width: 1/6
options:
- h1
- h2
- h3
- h4
- h5
- h6
text:
label: field.blocks.heading.text
type: writer
inline: true
width: 5/6
placeholder: field.blocks.heading.placeholder
Create a custom /site/blueprints/blocks/heading.yml
, copy the original code into it and make your changes as required.
This will then affect all headings in all block fields.
If you only want to make changes in a single block field, you can follow the docs here: