https://www.caniemail.com/tests/html-cellspacing.html
cellpadding and cellspacing
cellpaddingcellspacing
https://developer.mozilla.org/fr/docs/Web/API/HTMLTableElement/cellSpacing
HTMLTableElement : propriété cellSpacing - Les API Web | MDN
les apihtmltableelementcellspacingwebmdn
https://www.caniemail.com/features/html-cellspacing/
Can I email… cellspacing attribute
Supported in Apple Mail, Gmail, Outlook, Yahoo! Mail.
cellspacing attribute