Bugzilla – Bug 896
<summary> is required when <details> is used
Last modified: 2012-02-03 12:15:12 CET
http://www.whatwg.org/specs/web-apps/current-work/multipage/interactive-elements.html#the-details-element > Content model: One `summary` element followed by flow content. If I understand this correctly, http://html5.validator.nu/?doc=data%3Atext%2Fhtml%3Bcharset%3Dutf-8%2C%3C!DOCTYPE+html%3E%3Ctitle%3ETest%3C%2Ftitle%3E%3Cdetails%3Efoo%3C%2Fdetails%3E should show a validation error.
You do understand correctly, yes. My fault that it's not checking it correctly; 2 years ago I made this change: https://bitbucket.org/validator/syntax/changeset/0e21140dc318#chg-relaxng/applications.rnc details.inner = - ( legend.elem + ( summary.elem? , common.inner.flow ) Will fix it right now.
https://bitbucket.org/validator/syntax/changeset/7dbad8edfb8d Thanks for catching this and taking time to report it.