In Odoo, I have a scenario where I need to conditionally hide a field based on the content of an HTML field. However, the HTML field always contains <p><br/></p> tags, even when it's technically empty. Is there a way to check if the HTML field is "empty" (i.e., contains no meaningful content) and hide another field based on that in the XML side using attrs? How can I achieve this without relying on just the <p><br/></p> content?