$ mediawiki/vendor/bin/validate-json mediawiki/extensions/Gather/extension.json mediawiki/docs/extension.schema.json
JSON does not validate. Violations:
[ResourceModules.ext.gather.collection.editor] The property - @doc - is not defined and the definition does not allow additional properties
[ResourceModules.ext.gather.collection.editor] The property - targets - is not defined and the definition does not allow additional properties
[ResourceModules.ext.gather.collection.editor] The property - dependencies - is not defined and the definition does not allow additional properties
[ResourceModules.ext.gather.collection.editor] The property - messages - is not defined and the definition does not allow additional properties
[ResourceModules.ext.gather.collection.editor] The property - templates - is not defined and the definition does not allow additional properties
[ResourceModules.ext.gather.collection.editor] The property - scripts - is not defined and the definition does not allow additional properties
[ResourceModules.ext.gather.collection.editor] The property - styles - is not defined and the definition does not allow additional properties
[class] The property class is required
[ResourceModules.ext.gather.collection.editor] Failed to match at least one schema

		"ext.gather.collection.editor": {
			"targets": [
				"mobile",
				"desktop"
			],
			"@doc": "FIXME: ext.gather.styles gets loaded twice. See https://phabricator.wikimedia.org/T87871",
...