WordPress/wp-includes/blocks/columns/block.json

{
	"apiVersion": 2,
	"name": "core/columns",
	"title": "Columns",
	"category": "design",
	"description": "Display content in multiple columns, with blocks added to each column.",
	"textdomain": "default",
	"attributes": {
		"verticalAlignment": {
			"type": "string"
		},
		"isStackedOnMobile": {
			"type": "boolean",
			"default": true
		}
	},
	"supports": {
		"anchor": true,
		"align": [ "wide", "full" ],
		"html": false,
		"color": {
			"gradients": true,
			"link": true
		},
		"spacing": {
			"margin": [ "top", "bottom" ],
			"padding": true,
			"__experimentalDefaultControls": {
				"padding": true
			}
		}
	},
	"editorStyle": "wp-block-columns-editor",
	"style": "wp-block-columns"
}