John Elliot wrote:
That was a HTML4/XHTML1 rule that's been removed. An empty<ul></ul> is valid HTML5.
I wasn't sure if the empty<ul> was valid HTML5, or if the validator wasn't strict enough about it yet. In any event, I'm happy to take your word for it. If XHTML support is being deprecated, I won't argue for fixing the empty<ul> elements.
Those <ul> are an old discussion https://bugzilla.wikimedia.org/show_bug.cgi?id=24500