The shadow option needs to create a div on the fly to be able to retrieve the default shadow value. This commit makes sure these divs are also removed when no longer needed. This also simplifies the code and actually avoids that div creation when it is not needed. task-2752326 closes odoo/odoo#84324 X-original-commit: 309f03c011fc8e5e0bec9882af54a8147025118f Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com>