[QUESTION] How can I set default tagName

You can change the tagName of any component, at any moment, in this way:

const component = editor.getSelected(); // I use a selected one just as an example
component.set('tagName', 'article');
// or on some group of components
const components = editor.DomComponents.getWrapper().find('div');
components.forEach(component => component.set('tagName', 'article'));

You can also change it at the component level, in this way any new one of its type will get it by definition. Read more about Components and how to extend them. Basically, you would create/extend a component with a custom tagName in this way:

comps.addType('you-component', {
	model: defaultModel.extend({
		defaults: { ... 
			tagName: 'tr'
		},
		...
	}),
	view: defaultView,
})

works great! thanks @artf

Is there any way to change wrapper's tagName also?

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