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I would like to clarify that node's attributes collection is applied to the node object not to the check box element. Here
you may find a list with the valid HTML attributes that are rendered as HTML attributes. Any other custom attributes will not be rendered as HTML attributes. I would like to clarify that even the valid HTML attributes will be applied to the node element not to the check box element.
In this case the only solution will be to use templates and set the "data-bind" attribute to the check box element within the template.
Hope that this will be helpful.
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