Camel case in HTML tag attributes and jquery - doesn't work, why?

Question

Yes, there are similar questions, but they are about jquery adding lowercase attributes like here: Does the attr() in jQuery force lowercase?

But I have a different

Answer 1

Instead of using ".data()" you could just use ".attr()" to access the value of the attribute, then you could reference it by the name you've given it; like the following:

$(element).attr('data-projectId');